Code
P1616
DAEWOO
P — Powertrain
Main relay mal
Views:
UK: 2
EN: 2
RU: 3
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
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Code
P1616
KIA
P — Powertrain
Chassis Accelerator Sensor Signal Low Voltage
Views:
UK: 17
EN: 22
RU: 24
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
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Code
P1616
MINI
P — Powertrain
Engine control module (ECM) coding memory - check sum error
Views:
UK: 1
EN: 0
RU: 1
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
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Code
P1616
Other
P — Powertrain
SBDS Interactive Codes
Views:
UK: 19
EN: 20
RU: 23
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Workshop Manuals
Available brands with manuals
1
LAND ROVER 2
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualOfficial workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.
199,00 UAH
Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualWorkshop Manual Supplement and Body Repair Manual for the Land Rover Defender. Includes general specifications, maintenance schedules, tuning data and step‑by‑step repair procedures for engine, transmission, suspension, brakes, electrical and body repairs. Covers Defender models from 1999 and 2002 model years.
199,00 UAH
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Code
P1616
RAM
P — Powertrain
5V Output Reference Voltage 1 Low
Views:
UK: 1
EN: 1
RU: 3
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
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Code
P1616
SAAB
P — Powertrain
Rough Road Sensor Short To Ground
Views:
UK: 2
EN: 1
RU: 5
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
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Code
P1616
VOLKSWAGEN
P — Powertrain
Glow Plug Heater Indicator Circuit Short To B+
Views:
UK: 19
EN: 26
RU: 24
AI status
Completed
Completed
100%
Causes
- Faulty main (engine) relay (contacts stuck open/closed or coil failure)
- Blown fuse or fusible link in the ECU power feed
- Poor battery voltage or weak battery
- Corroded/loose relay socket or connector pins
- Damaged wiring or open/short to relay control or power circuits
- Faulty ground connection for ECM or relay coil
Symptoms
- MIL/Check Engine Lamp illuminated
- Engine cranks but will not start or intermittent no-start
- Complete loss of engine power or stalling
- No fuel pump or injector pulse when key is ON/CRANK
- Intermittent ECU power or resetting while driving
- Accessory or electrical anomalies tied to ECU feed
What to check
- Read and record freeze frame / stored codes; clear and retest
- Visual inspection of main relay, fuse box, relays and wiring for corrosion, overheating or damage
- Check battery voltage (should be ~12.4–12.8 V at rest; >11 V while cranking)
- Verify main relay presence and correct seating in socket; inspect pins
- Check ECU power and ground pins for battery voltage and good ground with key ON
- Swap main relay with a known-good relay of same type (if available) and retest
Signal parameters
- Relay coil control voltage: should be ~12 V when relay is commanded ON (key ON/START or ECU command)
- Relay output (supply) voltage: battery voltage (~12 V) present at relay output when energized
- Coil resistance: typical small-relay coil tens to a few hundred ohms (verify with service data)
- No-voltage condition: if relay not energized, relay output should be near 0 V relative to battery ground
- Continuity: low resistance between battery positive and ECM supply pin when relay closed
Diagnostic algorithm
- Connect scan tool, read freeze frame and pending codes. Note when and under what conditions code set.
- Visually inspect main relay, relay socket and harness for corrosion, melting, or water ingress. Check related fuses and fusible links.
- Verify battery voltage. Recharge or replace weak battery before continuing.
- With ignition ON (engine OFF), measure voltage at the relay coil control terminal and at the relay supply terminal. Compare to battery voltage.
- Crank engine while monitoring relay coil/control voltage to confirm proper activation under cranking.
- If relay is not being commanded but should be, trace control circuit back to immobilizer and ECM outputs; check for anti-theft inhibiting signal.
- Manually energize the relay (or apply 12 V to relay coil) with proper precautions: verify relay output feeds ECU and that engine attempts to start. If engine starts with relay manually energized, suspect control circuit or relay driver.
- Swap the main relay with a known-good identical relay (if available) and retest to confirm relay vs. wiring/ECM fault.
- Check continuity and resistance of power feed from battery + to relay output and from relay output to ECM supply pin; check grounds for low resistance to chassis negative.
- If wiring and relay test good but problem persists, check ECM power input circuitry and immobilizer interface or consult manufacturer service data. Replace faulty components per service procedure.
- After repair, clear codes and perform a driving/starting cycle to verify the issue does not return.
Likely causes
- Worn or failed main relay
- Loose/corroded connector at relay or ECM
- Blown ECU power fuse
- Open/short in battery feed or relay control wire
- Bad ground at ECU/relay
- Intermittent immobilizer cut-off
Fault status
Status
Main relay malfunction detected — ECU power feed or relay control circuit fault. Inspect main relay, fuses, connectors, wiring and grounds; verify immobilizer/ECM control.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
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0
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