Code
P1621
BUICK
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
CADILLAC
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
CHEVROLET
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for CHEVROLET
456
Browse 456 CHEVROLET manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
CHEVROLET
-
CHEVROLET: 2020
-
Camaro
- LS, Automatic Trans
- LS, Standard Trans
- LT, 2D Convertible, 2.0L Eng VIN X, Automatic Trans
- LT, 2D Convertible, 2.0L Eng VIN X, Standard Trans
- LT, 2D Convertible, 3.6L Eng VIN S, Automatic Trans
- LT, 2D Convertible, 3.6L Eng VIN S, Standard Trans
- LT, 2D Coupe, 2.0L Eng VIN X, Automatic Trans
- LT, 2D Coupe, 2.0L Eng VIN X, Standard Trans
- LT, 2D Coupe, 3.6L Eng VIN S, Automatic Trans
- LT, 2D Coupe, 3.6L Eng VIN S, Standard Trans
- LT1, 2D Convertible, Automatic Trans
- LT1, 2D Convertible, Standard Trans
- LT1, 2D Coupe, Automatic Trans
- LT1, 2D Coupe, Standard Trans
- SS, 2D Convertible, Automatic Trans
- SS, 2D Convertible, Standard Trans
- SS, 2D Coupe, Automatic Trans
- SS, 2D Coupe, Standard Trans
- ZL1, 2D Convertible, Automatic Trans
- ZL1, 2D Convertible, Standard Trans
- ZL1, 2D Coupe, Automatic Trans
- ZL1, 2D Coupe, Standard Trans
-
Colorado
- 2020 Colorado Base
- LT, 4D Pickup Crew Cab, 2.5L Eng VIN A · 2.5L Eng VIN A2020: Colorado LT
- LT, 4D Pickup Crew Cab, 2.8L Eng VIN 1, 4WD
- LT, 4D Pickup Crew Cab, 2.8L Eng VIN 1, RWD
- LT, 4D Pickup Crew Cab, 3.6L Eng VIN N, 4WD
- LT, 4D Pickup Crew Cab, 3.6L Eng VIN N, RWD
- LT, 4D Pickup Extra Cab, 2.5L Eng VIN A, 4WD
- LT, 4D Pickup Extra Cab, 2.5L Eng VIN A, RWD
- LT, 4D Pickup Extra Cab, 3.6L Eng VIN N, 4WD
- LT, 4D Pickup Extra Cab, 3.6L Eng VIN N, RWD
- WT, 4D Pickup Crew Cab, 2.5L Eng VIN A · 2.5L Eng VIN A2020: Colorado WT
- WT, 4D Pickup Crew Cab, 2.8L Eng VIN 1, 4WD
- WT, 4D Pickup Crew Cab, 2.8L Eng VIN 1, RWD
- WT, 4D Pickup Crew Cab, 3.6L Eng VIN N, 4WD
- WT, 4D Pickup Crew Cab, 3.6L Eng VIN N, RWD
- WT, 4D Pickup Extra Cab, 2.5L Eng VIN A, 4WD
- WT, 4D Pickup Extra Cab, 2.5L Eng VIN A, RWD
- WT, 4D Pickup Extra Cab, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Colorado WT
- WT, 4D Pickup Extra Cab, 3.6L Eng VIN N, 4WD
- WT, 4D Pickup Extra Cab, 3.6L Eng VIN N, RWD
- Z71, 4D Pickup Crew Cab, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Colorado Z71
- Z71, 4D Pickup Crew Cab, 3.6L Eng VIN N, 4WD
- Z71, 4D Pickup Crew Cab, 3.6L Eng VIN N, RWD
- Z71, 4D Pickup Extra Cab
- ZR2, 4D Pickup Crew Cab, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Colorado ZR2
- ZR2, 4D Pickup Crew Cab, 3.6L Eng VIN N · 3.6L Eng VIN N2020: Colorado ZR2
- ZR2, 4D Pickup Extra Cab, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Colorado ZR2
- ZR2, 4D Pickup Extra Cab, 3.6L Eng VIN N · 3.6L Eng VIN N2020: Colorado ZR2
-
Corvette
-
Express 2500
- Base, Van Cargo, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 2500 Base
- Base, Van Cargo, 4.3L Eng VIN P, Gas/Ethanol
- Base, Van Cargo, 4.3L Eng VIN P, Gas
- Base, Van Cargo, 6.0L Eng VIN B, Gas/Ethanol/CNG
- Base, Van Cargo, 6.0L Eng VIN B, Gas/Ethanol
- Base, Van Cargo, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 2500 Base
- Base, Van Cargo Extended, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 2500 Base
- Base, Van Cargo Extended, 4.3L Eng VIN P, Gas/Ethanol
- Base, Van Cargo Extended, 4.3L Eng VIN P, Gas
- Base, Van Cargo Extended, 6.0L Eng VIN B, Gas/Ethanol/CNG
- Base, Van Cargo Extended, 6.0L Eng VIN B, Gas/Ethanol
- Base, Van Cargo Extended, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 2500 Base
- LS, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 2500 LS
- LS, 4.3L Eng VIN P, Gas/Ethanol
- LS, 4.3L Eng VIN P, Gas
- LS, 6.0L Eng VIN B, Gas/Ethanol/CNG
- LS, 6.0L Eng VIN B, Gas/Ethanol
- LS, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 2500 LS
- LT, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 2500 LT
- LT, 4.3L Eng VIN P, Gas/Ethanol
- LT, 4.3L Eng VIN P, Gas
- LT, 6.0L Eng VIN B, Gas/Ethanol/CNG
- LT, 6.0L Eng VIN B, Gas/Ethanol
- LT, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 2500 LT
-
Express 3500
- Base, Cutaway, 4.3L Eng VIN P, Gas/Ethanol
- Base, Cutaway, 4.3L Eng VIN P, Gas
- Base, Cutaway, 6.0L Eng VIN B, Gas/Ethanol/CNG
- Base, Cutaway, 6.0L Eng VIN B, Gas
- Base, Cutaway, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 Base
- Base, Van Cargo, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 3500 Base
- Base, Van Cargo, 4.3L Eng VIN P, Gas/Ethanol
- Base, Van Cargo, 4.3L Eng VIN P, Gas
- Base, Van Cargo, 6.0L Eng VIN B, Gas/Ethanol/CNG
- Base, Van Cargo, 6.0L Eng VIN B, Gas/Ethanol
- Base, Van Cargo, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 Base
- Base, Van Cargo Extended, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 3500 Base
- Base, Van Cargo Extended, 4.3L Eng VIN P, Gas/Ethanol
- Base, Van Cargo Extended, 4.3L Eng VIN P, Gas
- Base, Van Cargo Extended, 6.0L Eng VIN B, Gas/Ethanol/CNG
- Base, Van Cargo Extended, 6.0L Eng VIN B, Gas/Ethanol
- Base, Van Cargo Extended, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 Base
- LS, Van Passenger, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 3500 LS
- LS, Van Passenger, 4.3L Eng VIN P, Gas/Ethanol
- LS, Van Passenger, 4.3L Eng VIN P, Gas
- LS, Van Passenger, 6.0L Eng VIN B, Gas/Ethanol/CNG
- LS, Van Passenger, 6.0L Eng VIN B, Gas/Ethanol
- LS, Van Passenger, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 LS
- LS, Van Passenger Extended, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 3500 LS
- LS, Van Passenger Extended, 4.3L Eng VIN P, Gas/Ethanol
- LS, Van Passenger Extended, 4.3L Eng VIN P, Gas
- LS, Van Passenger Extended, 6.0L Eng VIN B, Gas/Ethanol/CNG
- LS, Van Passenger Extended, 6.0L Eng VIN B, Gas/Ethanol
- LS, Van Passenger Extended, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 LS
- LT, Van Passenger, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 3500 LT
- LT, Van Passenger, 4.3L Eng VIN P, Gas/Ethanol
- LT, Van Passenger, 4.3L Eng VIN P, Gas
- LT, Van Passenger, 6.0L Eng VIN B, Gas/Ethanol/CNG
- LT, Van Passenger, 6.0L Eng VIN B, Gas/Ethanol
- LT, Van Passenger, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 LT
- LT, Van Passenger Extended, 2.8L Eng VIN 1 · 2.8L Eng VIN 12020: Express 3500 LT
- LT, Van Passenger Extended, 4.3L Eng VIN P, Gas/Ethanol
- LT, Van Passenger Extended, 4.3L Eng VIN P, Gas
- LT, Van Passenger Extended, 6.0L Eng VIN B, Gas/Ethanol/CNG
- LT, Van Passenger Extended, 6.0L Eng VIN B, Gas/Ethanol
- LT, Van Passenger Extended, 6.0L Eng VIN G · 6.0L Eng VIN G2020: Express 3500 LT
-
Silverado 1500
- Custom, 4D Pickup Crew Cab, 2.7L Eng VIN K, 4WD
- Custom, 4D Pickup Crew Cab, 2.7L Eng VIN K, RWD
- Custom, 4D Pickup Crew Cab, 4.3L Eng VIN H, 4WD
- Custom, 4D Pickup Crew Cab, 4.3L Eng VIN H, RWD
- Custom, 4D Pickup Crew Cab, 5.3L Eng VIN F, 4WD
- Custom, 4D Pickup Crew Cab, 5.3L Eng VIN F, RWD
- Custom, 4D Pickup Extra Cab, 2.7L Eng VIN K, 4WD
- Custom, 4D Pickup Extra Cab, 2.7L Eng VIN K, RWD
- Custom, 4D Pickup Extra Cab, 4.3L Eng VIN H, 4WD
- Custom, 4D Pickup Extra Cab, 4.3L Eng VIN H, RWD
- Custom, 4D Pickup Extra Cab, 5.3L Eng VIN F, 4WD
- Custom, 4D Pickup Extra Cab, 5.3L Eng VIN F, RWD
- Custom Trail Boss, 4D Pickup Crew Cab, 4.3L Eng VIN H · 4.3L Eng VIN H2020: Silverado 1500 Custom Trail Boss
- Custom Trail Boss, 4D Pickup Crew Cab, 5.3L Eng VIN F · 5.3L Eng VIN F2020: Silverado 1500 Custom Trail Boss
- Custom Trail Boss, 4D Pickup Crew Cab, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 Custom Trail Boss
- Custom Trail Boss, 4D Pickup Extra Cab, 4.3L Eng VIN H · 4.3L Eng VIN H2020: Silverado 1500 Custom Trail Boss
- Custom Trail Boss, 4D Pickup Extra Cab, 5.3L Eng VIN F · 5.3L Eng VIN F2020: Silverado 1500 Custom Trail Boss
- Custom Trail Boss, 4D Pickup Extra Cab, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 Custom Trail Boss
- High Country, 3.0L Eng VIN T, 4WD
- High Country, 3.0L Eng VIN T, RWD
- High Country, 5.3L Eng VIN D, 4WD
- High Country, 5.3L Eng VIN D, RWD
- High Country, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 High Country
- LT, 4D Pickup Crew Cab, 2.7L Eng VIN K, 4WD
- LT, 4D Pickup Crew Cab, 2.7L Eng VIN K, RWD
- LT, 4D Pickup Crew Cab, 3.0L Eng VIN T, 4WD
- LT, 4D Pickup Crew Cab, 3.0L Eng VIN T, RWD
- LT, 4D Pickup Crew Cab, 5.3L Eng VIN D, 4WD
- LT, 4D Pickup Crew Cab, 5.3L Eng VIN D, RWD
- LT, 4D Pickup Extra Cab, 2.7L Eng VIN K, 4WD
- LT, 4D Pickup Extra Cab, 2.7L Eng VIN K, RWD
- LT, 4D Pickup Extra Cab, 3.0L Eng VIN T, 4WD
- LT, 4D Pickup Extra Cab, 3.0L Eng VIN T, RWD
- LT, 4D Pickup Extra Cab, 5.3L Eng VIN D, 4WD
- LT, 4D Pickup Extra Cab, 5.3L Eng VIN D, RWD
- LT Trail Boss, 5.3L Eng VIN D · 5.3L Eng VIN D2020: Silverado 1500 LT Trail Boss
- LT Trail Boss, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 LT Trail Boss
- LTZ, 4D Pickup Crew Cab, 3.0L Eng VIN T, 4WD
- LTZ, 4D Pickup Crew Cab, 3.0L Eng VIN T, RWD
- LTZ, 4D Pickup Crew Cab, 5.3L Eng VIN D, 4WD
- LTZ, 4D Pickup Crew Cab, 5.3L Eng VIN D, RWD
- LTZ, 4D Pickup Crew Cab, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 LTZ
- LTZ, 4D Pickup Extra Cab, 3.0L Eng VIN T, 4WD
- LTZ, 4D Pickup Extra Cab, 3.0L Eng VIN T, RWD
- LTZ, 4D Pickup Extra Cab, 5.3L Eng VIN D, 4WD
- LTZ, 4D Pickup Extra Cab, 5.3L Eng VIN D, RWD
- LTZ, 4D Pickup Extra Cab, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 LTZ
- RST, 4D Pickup Crew Cab, 2.7L Eng VIN K, 4WD
- RST, 4D Pickup Crew Cab, 2.7L Eng VIN K, RWD
- RST, 4D Pickup Crew Cab, 3.0L Eng VIN T, 4WD
- RST, 4D Pickup Crew Cab, 3.0L Eng VIN T, RWD
- RST, 4D Pickup Crew Cab, 5.3L Eng VIN D, 4WD
- RST, 4D Pickup Crew Cab, 5.3L Eng VIN D, RWD
- RST, 4D Pickup Crew Cab, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 RST
- RST, 4D Pickup Extra Cab, 2.7L Eng VIN K, 4WD
- RST, 4D Pickup Extra Cab, 2.7L Eng VIN K, RWD
- RST, 4D Pickup Extra Cab, 3.0L Eng VIN T, 4WD
- RST, 4D Pickup Extra Cab, 3.0L Eng VIN T, RWD
- RST, 4D Pickup Extra Cab, 5.3L Eng VIN D, 4WD
- RST, 4D Pickup Extra Cab, 5.3L Eng VIN D, RWD
- RST, 4D Pickup Extra Cab, 6.2L Eng VIN L · 6.2L Eng VIN L2020: Silverado 1500 RST
- SSV, 4WD, Gas
- SSV, 4WD, Gas/Ethanol
- SSV, RWD, Gas
- SSV, RWD, Gas/Ethanol
- WT, 2D Pickup, 4.3L Eng VIN H, 4WD, Gas/Ethanol
- WT, 2D Pickup, 4.3L Eng VIN H, 4WD, Gas
- WT, 2D Pickup, 4.3L Eng VIN H, RWD, Gas/Ethanol
- WT, 2D Pickup, 4.3L Eng VIN H, RWD, Gas
- WT, 2D Pickup, 5.3L Eng VIN F, 4WD, Gas/Ethanol
- WT, 2D Pickup, 5.3L Eng VIN F, 4WD, Gas
- WT, 2D Pickup, 5.3L Eng VIN F, RWD, Gas/Ethanol
- WT, 2D Pickup, 5.3L Eng VIN F, RWD, Gas
- WT, 4D Pickup Crew Cab, 2.7L Eng VIN K, 4WD
- WT, 4D Pickup Crew Cab, 2.7L Eng VIN K, RWD
- WT, 4D Pickup Crew Cab, 4.3L Eng VIN H, 4WD, Gas/Ethanol
- WT, 4D Pickup Crew Cab, 4.3L Eng VIN H, 4WD, Gas
- WT, 4D Pickup Crew Cab, 4.3L Eng VIN H, RWD, Gas/Ethanol
- WT, 4D Pickup Crew Cab, 4.3L Eng VIN H, RWD, Gas
- WT, 4D Pickup Crew Cab, 5.3L Eng VIN F, 4WD, Gas/Ethanol
- WT, 4D Pickup Crew Cab, 5.3L Eng VIN F, 4WD, Gas
- WT, 4D Pickup Crew Cab, 5.3L Eng VIN F, RWD, Gas/Ethanol
- WT, 4D Pickup Crew Cab, 5.3L Eng VIN F, RWD, Gas
- WT, 4D Pickup Extra Cab, 2.7L Eng VIN K, 4WD
- WT, 4D Pickup Extra Cab, 2.7L Eng VIN K, RWD
- WT, 4D Pickup Extra Cab, 4.3L Eng VIN H, 4WD, Gas/Ethanol
- WT, 4D Pickup Extra Cab, 4.3L Eng VIN H, 4WD, Gas
- WT, 4D Pickup Extra Cab, 4.3L Eng VIN H, RWD, Gas/Ethanol
- WT, 4D Pickup Extra Cab, 4.3L Eng VIN H, RWD, Gas
- WT, 4D Pickup Extra Cab, 5.3L Eng VIN F, 4WD, Gas/Ethanol
- WT, 4D Pickup Extra Cab, 5.3L Eng VIN F, 4WD, Gas
- WT, 4D Pickup Extra Cab, 5.3L Eng VIN F, RWD, Gas/Ethanol
- WT, 4D Pickup Extra Cab, 5.3L Eng VIN F, RWD, Gas
-
Silverado 2500 HD
- Custom, 4D Pickup Crew Cab, 4WD
- Custom, 4D Pickup Crew Cab, RWD
- Custom, 4D Pickup Extra Cab, 4WD
- Custom, 4D Pickup Extra Cab, RWD
- High Country, 6.6L Eng VIN 7 · 6.6L Eng VIN 72020: Silverado 2500 HD High Country
- High Country, 6.6L Eng VIN Y · 6.6L Eng VIN Y2020: Silverado 2500 HD High Country
- LT, 2D Pickup, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 2D Pickup, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 2D Pickup, 6.6L Eng VIN 7, RWD
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, RWD
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, RWD
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LTZ, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD
- LTZ, 4D Pickup Crew Cab, 6.6L Eng VIN 7, RWD
- LTZ, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD
- LTZ, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD
- LTZ, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD
- LTZ, 4D Pickup Extra Cab, 6.6L Eng VIN 7, RWD
- LTZ, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD
- LTZ, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD
- WT, 2D Pickup, 6.6L Eng VIN 7, 4WD
- WT, 2D Pickup, 6.6L Eng VIN 7, RWD
- WT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGM
- WT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGU
- WT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, RWD
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, RWD
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
-
Silverado 3500 HD
- High Country, 6.6L Eng VIN 7 · 6.6L Eng VIN 72020: Silverado 3500 HD High Country
- High Country, 6.6L Eng VIN Y · 6.6L Eng VIN Y2020: Silverado 3500 HD High Country
- LT, 2D Cab Chassis, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 2D Cab Chassis, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 2D Cab Chassis, 6.6L Eng VIN 7, RWD
- LT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 2D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 2D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LT, 2D Pickup, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 2D Pickup, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 2D Pickup, 6.6L Eng VIN 7, RWD
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LT, 4D Cab Chassis, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 4D Cab Chassis, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 4D Cab Chassis, 6.6L Eng VIN 7, RWD
- LT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 4D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, RWD
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, RWD
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- LT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- LTZ, 6.6L Eng VIN 7, 4WD
- LTZ, 6.6L Eng VIN 7, RWD
- LTZ, 6.6L Eng VIN Y, 4WD
- LTZ, 6.6L Eng VIN Y, RWD
- WT, 2D Cab Chassis, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- WT, 2D Cab Chassis, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- WT, 2D Cab Chassis, 6.6L Eng VIN 7, RWD
- WT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- WT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- WT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- WT, 2D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- WT, 2D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 2D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- WT, 2D Pickup, 6.6L Eng VIN 7, 4WD
- WT, 2D Pickup, 6.6L Eng VIN 7, RWD
- WT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGM
- WT, 2D Pickup, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGU
- WT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 2D Pickup, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- WT, 4D Cab Chassis, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
- WT, 4D Cab Chassis, 6.6L Eng VIN 7, 4WD, Part Time T/Case Control
- WT, 4D Cab Chassis, 6.6L Eng VIN 7, RWD
- WT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGM
- WT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Automatic T/Case Control, Trans Mfr CD 10L1000/MGU
- WT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGM
- WT, 4D Cab Chassis, 6.6L Eng VIN Y, 4WD, Part Time T/Case Control, Trans Mfr CD 10L1000/MGU
- WT, 4D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 4D Cab Chassis, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, RWD
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Crew Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, RWD
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, 4WD, Trans Mfr CD 10L1000/MGU
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGM
- WT, 4D Pickup Extra Cab, 6.6L Eng VIN Y, RWD, Trans Mfr CD 10L1000/MGU
-
Suburban
- FL, 4WD, Gas
- FL, 4WD, Gas/Ethanol
- FL, RWD, Gas
- FL, RWD, Gas/Ethanol
- LS, 4WD, Gas
- LS, 4WD, Gas/Ethanol
- LS, RWD, Gas
- LS, RWD, Gas/Ethanol
- LT, 4WD, Gas
- LT, 4WD, Gas/Ethanol
- LT, RWD, Gas
- LT, RWD, Gas/Ethanol
- Premier, 5.3L Eng VIN C, 4WD, Gas/Ethanol
- Premier, 5.3L Eng VIN C, 4WD, Gas
- Premier, 5.3L Eng VIN C, RWD, Gas/Ethanol
- Premier, 5.3L Eng VIN C, RWD, Gas
- Premier, 6.2L Eng VIN J, 4WD
- Premier, 6.2L Eng VIN J, RWD
-
Tahoe
- FL, 4WD, Gas
- FL, 4WD, Gas/Ethanol
- FL, RWD, Gas
- FL, RWD, Gas/Ethanol
- LS, 4WD, Gas
- LS, 4WD, Gas/Ethanol
- LS, RWD, Gas
- LS, RWD, Gas/Ethanol
- LT, 4WD, Gas
- LT, 4WD, Gas/Ethanol
- LT, RWD, Gas
- LT, RWD, Gas/Ethanol
- PPV, 4WD, Gas
- PPV, 4WD, Gas/Ethanol
- PPV, RWD, Gas
- PPV, RWD, Gas/Ethanol
- Premier, 5.3L Eng VIN C, 4WD, Gas/Ethanol
- Premier, 5.3L Eng VIN C, 4WD, Gas
- Premier, 5.3L Eng VIN C, RWD, Gas/Ethanol
- Premier, 5.3L Eng VIN C, RWD, Gas
- Premier, 6.2L Eng VIN J, 4WD
- Premier, 6.2L Eng VIN J, RWD
- SSV, Gas
- SSV, Gas/Ethanol
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Code
P1621
CITROEN
P — Powertrain
Inside ECU (CAN)
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
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Code
P1621
DAEWOO
P — Powertrain
Fuel cut valve mal
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for DAEWOO
75
Browse 75 DAEWOO manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
DAEWOO
-
DAEWOO: 2001
-
Leganza
-
DAEWOO: 2000
-
Leganza
-
DAEWOO: 1999
-
Lanos
- S, 2D Hatchback, Automatic
- S, 2D Hatchback, Standard
- S, 4D Sedan, Automatic
- S, 4D Sedan, Standard
- SE, 2D Hatchback, Automatic
- SE, 2D Hatchback, Standard
- SE, 4D Sedan, Automatic
- SE, 4D Sedan, Standard
- SX, 2D Hatchback, Automatic
- SX, 2D Hatchback, Standard
- SX, 4D Sedan, Automatic
- SX, 4D Sedan, Standard
-
Leganza
-
Nubira
- CDX, 4D Hatchback, Automatic
- CDX, 4D Hatchback, Standard
- CDX, 4D Sedan, Automatic
- CDX, 4D Sedan, Standard
- CDX, 4D Wagon, Automatic
- CDX, 4D Wagon, Standard
- SX, 4D Hatchback, Automatic
- SX, 4D Hatchback, Standard
- SX, 4D Sedan, Automatic
- SX, 4D Sedan, Standard
- SX, 4D Wagon, Automatic
- SX, 4D Wagon, Standard
-
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Code
P1621
DS
P — Powertrain
Inside ECU (CAN)
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
GM
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
GMC
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
HUMMER
P — Powertrain
Control Module Long Term Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for HUMMER
138
Browse 138 HUMMER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
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HUMMER: 1993
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Code
P1621
ISUZU
P — Powertrain
Control Module Long Term Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for ISUZU
86
Browse 86 ISUZU manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
ISUZU
-
ISUZU: 2008
-
ISUZU: 2006
-
i-350
-
ISUZU: 2005
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Code
P1621
LAND ROVER
P — Powertrain
Mau operation of the input circuit of the motor control module
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for LAND ROVER
320
Browse 320 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
LAND ROVER
-
LAND ROVER: 2022
-
Defender
- 90
- 90
- 90 S
- 90 S
- 90 V8
- 90 V8
- 90 V8 Carpathian Edition
- 90 V8 Carpathian Edition
- 90 X
- 90 X
- 90 X-Dynamic HSE
- 90 X-Dynamic HSE
- 90 X-Dynamic S
- 90 X-Dynamic S
- 90 X-Dynamic SE
- 90 X-Dynamic SE
- 110
- 110
- 110 S
- 110 S
- 110 SE
- 110 SE
- 110 V8
- 110 V8
- 110 V8 Carpathian Edition
- 110 V8 Carpathian Edition
- 110 X
- 110 X
- 110 X-Dynamic SE
- 110 X-Dynamic SE
- 110 XS Edition
- 110 XS Edition
-
Discovery
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Discovery R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Discovery R-Dynamic S
- S
- S
-
Discovery Sport
-
Range Rover
- Autobiography, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover Autobiography
- Autobiography, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover Autobiography
- 2022 Range Rover Base
- 2022 Range Rover Base
- First Edition
- First Edition
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover HSE Westminster
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover HSE Westminster
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover SE
- SE, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover SE
- SE, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover SE
- SV
- SV
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
- SVAutobiography Dynamic Blk.
- SVAutobiography Dynamic Blk.
-
Range Rover Evoque
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar S
-
-
LAND ROVER: 2021
-
Discovery
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Discovery R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Discovery R-Dynamic S
- S
- S
-
Discovery Sport
-
Range Rover
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Autobiography
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Autobiography
- Autobiography Fifty Edition
- Autobiography Fifty Edition
- 2021 Range Rover Base
- 2021 Range Rover Base
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover HSE
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover HSE
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover HSE Westminster
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover HSE Westminster
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
- SVAutobiography Dynamic Blk.
- SVAutobiography Dynamic Blk.
-
Range Rover Evoque
-
Range Rover Sport
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography Dynamic
- HSE Dynamic
- HSE Dynamic
- HSE Silver Edition, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Sport HSE Silver Edition
- HST
- HST
- SE
- SE
- SVR
- SVR
- SVR Carbon Edition
- SVR Carbon Edition
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar S
-
LAND ROVER: 2020
-
Defender
- 90 First Edition
- 90 First Edition
- 110 First Edition
- 110 First Edition
- 110 HSE
- 110 HSE
- 110 S
- 110 S
- 110 SE
- 110 SE
- 110 X
- 110 X
- 110, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Defender 110
- 110, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Defender 110
- 110, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Defender 110
- 110, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Defender 110
-
Discovery
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE
- HSE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE
- HSE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE
- HSE Luxury, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE Luxury
- Landmark
- Landmark
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery SE
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery SE
- SE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery SE
- SE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery SE
-
Range Rover
- Autobiography
- Autobiography
- Base, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Base
- Base, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Base
- Base, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Base
- Base, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Base
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover HSE
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover HSE
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
-
Range Rover Evoque
-
Range Rover Sport
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport Autobiography Dynamic
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport HSE
- HSE Dynamic
- HSE Dynamic
- HSE PHEV
- HSE PHEV
- HST
- HST
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport SE
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport SE
- SVR
- SVR
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar S
- S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar S
- S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar S
- SVAutobiography Dyn.
- SVAutobiography Dyn.
-
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Code
P1621
MAZDA
P — Powertrain
Immobilizer System Fault
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
MITSUBISHI
P — Powertrain
Injection pump (TCV)
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for MITSUBISHI
406
Browse 406 MITSUBISHI manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
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- ES, AWD
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-
-
MITSUBISHI: 2021
-
MITSUBISHI: 2020
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Code
P1621
OLDSMOBILE
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
Other
P — Powertrain
Control Module Long Term Memory Performance/ Immobilizer Code Words Do Not Match
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Brands with available manuals
8,280
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Code
P1621
PEUGEOT
P — Powertrain
Inside ECU (CAN)
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
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Code
P1621
SAAB
P — Powertrain
Internal Control Module Malfunction
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
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Code
P1621
SATURN
P — Powertrain
PCM Memory Performance
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
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Code
P1621
VOLKSWAGEN
P — Powertrain
Engine Coolant Temperature Signal Short To Ground
AI status
Completed
Completed
100%
Causes
- Low or unstable battery/charging system voltage
- Poor power or ground connections to the PCM
- Corroded/damaged PCM connector pins or wiring harness faults
- Internal PCM memory or processor failure (EEPROM/KAM/ROM)
- Interrupted programming or failed software update
- CAN/LIN network communication errors or bus faults
Symptoms
- MIL (Check Engine Light) illuminated
- Stored or recurring memory-related fault codes
- Vehicle may lose learned fuel trims, idle adaptations, or shift strategy
- Intermittent or persistent drivability issues (stalling, poor running, limp‑home mode)
- Difficulty starting or no‑start in severe cases
- Unable to clear codes or codes return immediately after clearing
What to check
- Read all stored and pending codes and freeze frame data with a capable scan tool
- Verify battery state-of-charge and battery terminal condition; measure resting voltage (should be ~12.4–12.8 V)
- Inspect PCM power and ground circuits, fuses, and fusible links for continuity and proper voltage
- Visually inspect PCM connector for corrosion, bent pins, water intrusion, or physical damage
- Check charging system voltage with engine running (13.5–14.8 V typical)
- Scan for network communication errors on CAN/LIN bus and related module availability
Signal parameters
- Battery/resting voltage: ~12.4–12.8 V (engine off)
- Charging voltage: ~13.5–14.8 V (engine running)
- Cranking voltage: should not fall below ~9.5 V during cranking under normal conditions
- PCM power supply test: battery voltage present at PCM 12V power terminal
- PCM ground:
- CAN bus idle voltages (depending on vehicle): CAN_H ~2.5–3.5 V, CAN_L ~1.5–2.5 V (differential ~2 V); verify using OEM specs
Diagnostic algorithm
- Connect a quality scan tool and record all active/pending/history codes and freeze frame; note accompanying codes that may point to power/communication faults.
- Verify battery condition and fully charge battery if low; ensure good terminal connections and test charging system under load.
- With ignition off, inspect PCM connector and wiring harness for corrosion, damaged insulation, water intrusion, or bent pins; repair any issues found.
- With ignition on, verify battery voltage at PCM power terminal(s) and check continuity/resistance to chassis ground from PCM ground terminals.
- Check for CAN/LIN communication faults: verify module presence on network and look for bus errors or shorts to battery/ground; repair wiring as needed.
- If power/ground and communications are good, attempt to clear codes and perform ignition cycles; if code returns immediately, suspect internal PCM memory fault.
- Check for recent reflash attempts or interrupted programming; if software is suspect, obtain latest OEM calibration and attempt reflash using manufacturer tools and procedures (follow anti-theft and immobilizer steps).
- If reprogramming fails or memory errors persist despite good power/ground and communications, consider PCM replacement with correct part number and OEM programming; follow OEM immobilizer and module matching procedures.
- After repair or reprogramming, clear codes and perform a road test and verification; re-check for return of P1621 and related codes.
Likely causes
- Weak or discharged battery or poor battery terminal connection
- Loose, corroded or damaged PCM power/ground connector or wiring
- Failed internal PCM keep‑alive memory (KAM/EEPROM) or processor
- Recent failed or incomplete PCM reflash/programming
Fault status
Status
PCM memory/keep‑alive memory performance fault detected — corrupted or unreliable PCM memory or related internal module fault. May require verification of power/ground, network communication, reprogramming, or module replacement.
Repair difficulty: Hard
Diagnostic time: 1.5-4.0 hours
Similar codes
Repair manuals
Manual library for VOLKSWAGEN
284
Browse 284 VOLKSWAGEN manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
VOLKSWAGEN
-
VOLKSWAGEN: 2021
-
Atlas
- S, AWD
- S, FWD
- SE, 2.0L Eng VIN P, AWD
- SE, 2.0L Eng VIN P, FWD
- SE, 3.6L Eng VIN R, AWD
- SE, 3.6L Eng VIN R, FWD
- SEL, 2.0L Eng VIN P · 2.0L Eng VIN P2021: Atlas SEL
- SEL, 3.6L Eng VIN R, AWD
- SEL, 3.6L Eng VIN R, FWD
- SEL Premium, 2.0L Eng VIN P · 2.0L Eng VIN P2021: Atlas SEL Premium
- SEL Premium, 3.6L Eng VIN R · 3.6L Eng VIN R2021: Atlas SEL Premium
- SEL Premium R-Line
- SEL R-Line, AWD
- SEL R-Line, FWD
- SE R-Line, AWD
- SE R-Line, FWD
-
Atlas Cross Sport
- S, AWD
- S, FWD
- SE, 2.0L Eng VIN C, AWD
- SE, 2.0L Eng VIN C, FWD
- SE, 3.6L Eng VIN E, AWD
- SE, 3.6L Eng VIN E, FWD
- SEL, 2.0L Eng VIN C · 2.0L Eng VIN C2021: Atlas Cross Sport SEL
- SEL, 3.6L Eng VIN E, AWD
- SEL, 3.6L Eng VIN E, FWD
- SEL Premium, 2.0L Eng VIN C · 2.0L Eng VIN C2021: Atlas Cross Sport SEL Premium
- SEL Premium, 3.6L Eng VIN E · 3.6L Eng VIN E2021: Atlas Cross Sport SEL Premium
- SEL Premium R-Line
- SEL R-Line, AWD
- SEL R-Line, FWD
- SE R-Line, AWD
- SE R-Line, FWD
-
VOLKSWAGEN: 2020
-
Atlas
- S, 2.0L Eng VIN P · 2.0L Eng VIN P2020: Atlas S
- S, 3.6L Eng VIN R · 3.6L Eng VIN R2020: Atlas S
- SE, 2.0L Eng VIN P · 2.0L Eng VIN P2020: Atlas SE
- SE, 3.6L Eng VIN R, AWD
- SE, 3.6L Eng VIN R, FWD
- SEL, 2.0L Eng VIN P · 2.0L Eng VIN P2020: Atlas SEL
- SEL, 3.6L Eng VIN R, AWD
- SEL, 3.6L Eng VIN R, FWD
- SEL Premium
- SEL R-Line, AWD
- SEL R-Line, FWD
- SE R-Line, AWD
- SE R-Line, FWD
-
Atlas Cross Sport
- S, AWD
- S, FWD
- SE, 2.0L Eng VIN C, AWD
- SE, 2.0L Eng VIN C, FWD
- SE, 3.6L Eng VIN E, AWD
- SE, 3.6L Eng VIN E, FWD
- SEL, 2.0L Eng VIN C, AWD
- SEL, 2.0L Eng VIN C, FWD
- SEL, 3.6L Eng VIN E, AWD
- SEL, 3.6L Eng VIN E, FWD
- SEL Premium
- SEL Premium R-Line
- SEL R-Line, AWD
- SEL R-Line, FWD
- SE R-Line, AWD
- SE R-Line, FWD
-
Jetta
- GLI Autobahn, Automatic DCT Trans
- GLI Autobahn, Standard Trans
- GLI S, Automatic DCT Trans
- GLI S, Standard Trans
- R-Line, 1.4L Eng VIN 5, Automatic Trans
- R-Line, 1.4L Eng VIN 5, Standard Trans
- R-Line, 1.4L Eng VIN B · 1.4L Eng VIN B2020: Jetta R-Line
- S, 1.4L Eng VIN 5, Automatic Trans
- S, 1.4L Eng VIN 5, Standard Trans
- S, 1.4L Eng VIN B · 1.4L Eng VIN B2020: Jetta S
- SE, 1.4L Eng VIN 5 · 1.4L Eng VIN 52020: Jetta SE
- SE, 1.4L Eng VIN B · 1.4L Eng VIN B2020: Jetta SE
- SEL, 1.4L Eng VIN 5 · 1.4L Eng VIN 52020: Jetta SEL
- SEL, 1.4L Eng VIN B · 1.4L Eng VIN B2020: Jetta SEL
- SEL Premium, 1.4L Eng VIN 5 · 1.4L Eng VIN 52020: Jetta SEL Premium
- SEL Premium, 1.4L Eng VIN B · 1.4L Eng VIN B2020: Jetta SEL Premium
-
VOLKSWAGEN: 2019
-
e-Golf
-
Golf Alltrack
- S, Eng CD CXBA, Automatic DCT Trans
- S, Eng CD CXBA, Standard Trans
- S, Eng CD CXBB, Automatic DCT Trans
- S, Eng CD CXBB, Standard Trans
- SE, Eng CD CXBA, Automatic DCT Trans
- SE, Eng CD CXBA, Standard Trans
- SE, Eng CD CXBB, Automatic DCT Trans
- SE, Eng CD CXBB, Standard Trans
- SEL, Eng CD CXBA, Automatic DCT Trans
- SEL, Eng CD CXBA, Standard Trans
- SEL, Eng CD CXBB, Automatic DCT Trans
- SEL, Eng CD CXBB, Standard Trans
-
Jetta
- GLI 35th Anniversary Edition, Automatic DCT Trans
- GLI 35th Anniversary Edition, Standard Trans
- GLI Autobahn, Automatic DCT Trans
- GLI Autobahn, Standard Trans
- GLI S, Automatic DCT Trans
- GLI S, Standard Trans
- R-Line, 1.4L Eng VIN 5 · 1.4L Eng VIN 52019: Jetta R-Line
- R-Line, 1.4L Eng VIN B · 1.4L Eng VIN B2019: Jetta R-Line
- S, 1.4L Eng VIN 5, Automatic Trans
- S, 1.4L Eng VIN 5, Standard Trans
- S, 1.4L Eng VIN B · 1.4L Eng VIN B2019: Jetta S
- SE, 1.4L Eng VIN 5 · 1.4L Eng VIN 52019: Jetta SE
- SE, 1.4L Eng VIN B · 1.4L Eng VIN B2019: Jetta SE
- SEL, 1.4L Eng VIN 5 · 1.4L Eng VIN 52019: Jetta SEL
- SEL, 1.4L Eng VIN B · 1.4L Eng VIN B2019: Jetta SEL
- SEL Premium, 1.4L Eng VIN 5 · 1.4L Eng VIN 52019: Jetta SEL Premium
- SEL Premium, 1.4L Eng VIN B · 1.4L Eng VIN B2019: Jetta SEL Premium
-
VOLKSWAGEN: 2018
-
Atlas
- Launch Edition, AWD
- Launch Edition, FWD
- S, 2.0L Eng VIN P · 2.0L Eng VIN P2018: Atlas S
- S, 3.6L Eng VIN R, AWD
- S, 3.6L Eng VIN R, FWD
- SE, 2.0L Eng VIN P · 2.0L Eng VIN P2018: Atlas SE
- SE, 3.6L Eng VIN R, AWD
- SE, 3.6L Eng VIN R, FWD
- SEL, 2.0L Eng VIN P · 2.0L Eng VIN P2018: Atlas SEL
- SEL, 3.6L Eng VIN R, AWD
- SEL, 3.6L Eng VIN R, FWD
- SEL Premium, AWD
- SEL Premium, FWD
-
Golf Alltrack
- S, Eng CD CXBA, Automatic DCT Trans
- S, Eng CD CXBA, Standard Trans
- S, Eng CD CXBB, Automatic DCT Trans
- S, Eng CD CXBB, Standard Trans
- SE, Eng CD CXBA, Automatic DCT Trans
- SE, Eng CD CXBA, Standard Trans
- SE, Eng CD CXBB, Automatic DCT Trans
- SE, Eng CD CXBB, Standard Trans
- SEL, Eng CD CXBA
- SEL, Eng CD CXBB
-
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