Code
P1251
JAGUAR
P — Powertrain
Throttle Position
Views:
UK: 15
EN: 34
RU: 21
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
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Code
P1251
LAND ROVER
P — Powertrain
Engine relay defective accelerator
Views:
UK: 2
EN: 9
RU: 3
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
Similar codes
Workshop Manuals
Repair manuals for LAND ROVER
3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
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Code
P1251
MAZDA
P — Powertrain
Air Mixture Solenoid Circuit
Views:
UK: 14
EN: 27
RU: 21
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
Similar codes
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Code
P1251
Other
P — Powertrain
Air Mixture Solenoid Circuit Malfunction
Views:
UK: 16
EN: 37
RU: 19
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
Similar codes
Workshop Manuals
Available brands with manuals
2
AUDI 11
6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)
Workshop ManualAudi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002
Workshop ManualAUDI A3 (2004) Workshop Manual — 2.0L FSI Turbo (4‑cyl, 4‑valve) Engine, Mechanics — Edition 03.2017
Workshop ManualAudi A3 2004 — Electrical System (Workshop Manual, Edition 02.2018)
Workshop ManualAudi A4 / A4 Cabriolet – 4.2 l V8 (5‑valve, timing chains) – Workshop Manual (Mechanics) – Edition 04.2007
Workshop ManualAudi A4 / A4 Cabriolet — Auxiliary Heater Workshop Manual (Edition 08.2004)
Workshop ManualAudi A4 / A4 Cabriolet (1.8T 4‑cyl turbo) — Motronic Injection & Ignition System Service Manual (Edition 01.2015)
Workshop ManualAudi A8 (2003) — Electrical System Workshop Manual (Edition 08.2014)
Workshop ManualAudi Q4 e-tron (Type F4) - Self-study Programme SSP 685
Workshop ManualAudi Q8 (2018) — Electrical System Workshop Manual (Edition 05.2019)
Workshop ManualAudi Servicing Manual — 7‑Speed Dual Clutch Transmission 0CJ / 0CL / 0CK / 0DN / 0DP / 0HL (Edition 05.2018)
Workshop ManualLAND ROVER 3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
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Code
P1251
RAM
P — Powertrain
Vacuum Reservoir Control Circuit Low
Views:
UK: 1
EN: 7
RU: 3
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
Similar codes
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Code
P1251
SAAB
P — Powertrain
Check Engine Lamp, Output From Control Module Low
Views:
UK: 2
EN: 5
RU: 4
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
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👍 Like
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Code
P1251
VOLKSWAGEN
P — Powertrain
Start Of Injection Solenoid Circuit Short To B+
Views:
UK: 13
EN: 30
RU: 21
AI status
Completed
Completed
100%
Causes
- Faulty throttle position sensor (TPS) or potentiometer in throttle body
- Damaged wiring or poor connector contacts in TPS reference/ground/signal circuits
- Corroded or contaminated throttle body electrical connector
- Throttle body actuator/mechanism binding or carbon buildup affecting sensor reading
- Incorrect reference voltage from ECM or poor sensor ground
- Faulty ECM or intermittent internal fault
Symptoms
- Malfunction Indicator Lamp (MIL)/check engine light illuminated
- Reduced engine power or limp-home mode (limited throttle)
- Poor or delayed throttle response, hesitation on acceleration
- High, low or erratic idle speed
- Stalling at idle or when coming to stop
- Possible difficulty starting or abnormal engine behavior after throttle adaptation/reset
What to check
- Read stored DTCs and freeze-frame data with a capable scanner; note conditions when code set
- Check for additional related codes (pedal position, throttle actuator, CAN communication)
- Visually inspect throttle body connector and wiring for damage, corrosion, or water ingress
- Backprobe TPS signal, reference (typically +5V) and ground with key ON; compare to expected voltages
- Scan-live: monitor throttle position vs. accelerator pedal position and expected ranges from idle to wide-open throttle
- Check for trouble in the throttle body actuator (run actuator tests if scanner supports)
Signal parameters
- Key ON engine OFF: TPS voltage typically ~0.5–1.0 V at closed throttle (manufacturer-specific)
- Wide-open throttle voltage typically ~4.0–4.5 V
- Signal should change smoothly with pedal movement; no sudden drops/spikes or intermittent open circuit
- Reference supply typically +5 V (steady) and ground near 0 V; check for noise/voltage deviation
- Compare TPS A and B (if dual sensors) — they should correlate and be inverse/parallel per design
Diagnostic algorithm
- Capture codes and freeze-frame; record live data of TPS, accelerator pedal sensors (APPS), throttle actuator position and battery voltage.
- Perform a careful visual inspection of throttle body, connector, and wiring harness; repair any damaged wiring or corroded connectors.
- With a digital multimeter, measure TPS reference, signal and ground at the connector with key ON. Confirm reference ≈5 V, ground ≈0 V, and closed-throttle signal within expected low-voltage range.
- Slowly move throttle (or have technician operate pedal) while watching live TPS voltage — confirm smooth, linear change without jumps. If jumps/noise, suspect TPS or wiring.
- If wiring/connector OK but signal out-of-range or non-linear, remove and bench-test/replace throttle position sensor or throttle body assembly as required.
- If vehicle has dual sensors (A/B) or redundant APPS, compare both sensor outputs and check correlation — if mismatch, replace failing component.
- After repair or sensor replacement, clear codes and perform throttle adaptation/learn procedure per Jaguar service manual, then road-test to verify.
- If all checks pass and problem persists, investigate ECM power/ground circuits; consider module testing or replacement as final step.
Likely causes
- Wiring harness chafing at steering/engine, causing intermittent signal
- Contaminated connector pins at throttle body
- TPS internal wear or failed potentiometer
- Throttle body assembly failing or motor/gear damage
- Failed ECM less likely but possible if all else checks good
Fault status
Status
Throttle Position Circuit — sensor/circuit out of expected range or performance mismatch detected by ECM. Condition stored as trouble code; may be active or pending and can cause reduced power or limp-home behavior.
Repair difficulty: Medium
Diagnostic time: 1-3 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email