P0686
Engine Control Module Voltage Error Low
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0686 means
- The fault code P0686 refers to a low voltage signal in the power relay control circuit for the engine control module or powertrain control module. This may cause the vehicle to experience various problems including reduced performance, starting issues, or stalling.
Possible symptoms
- Illuminated check engine light
- Reduced performance
- Engine may not start or may stall
- Various warning lights may appear on the dashboard
Possible causes
- Faulty power relay control circuit
- Poor electrical connections in the circuit
- Failed engine control module or powertrain control module
- Blown fuse in the circuit
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
- Check and repair any damaged wiring or connections in the power relay control circuit
- Replace the power relay if necessary
- Replace the engine control module or powertrain control module if required
- Check and replace any blown fuses in the circuit
Free on OBD DashX
P0686 on OBD DashX
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