P0685
Electronic Control Module Power Control Circuit Malfunction
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0685 means
- The fault code P0685 indicates that there is an issue with the power relay control circuit that controls the Engine Control Module/Powertrain Control Module (ECM/PCM). This may cause the vehicle to not start or the engine to run poorly.
Possible symptoms
- Engine may not start
- Illuminated check engine light
- Poor engine performance
- Reduced fuel efficiency
- Stalling or hesitation during acceleration
Possible causes
- Failed ECM/PCM power relay
- Faulty wiring or connections in the circuit
- Loose or corroded electrical connections
- Failed ECM/PCM
Related parts
- Engine Control Module (ECM): ECM is the part of the car computer that controls the engine system and performance. Problems lead to poor fuel economy, engine stalling & unwanted engine vibrations
Possible solutions
- Replace the ECM/PCM power relay
- Check and repair any damaged wiring or connections
- Tighten or clean any loose or corroded electrical connections
- Replace the ECM/PCM if necessary
Free on OBD DashX
P0685 on OBD DashX
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