P0685 – ECM/PCM Power Relay Control Circuit/Open
- System
- ECM
- Dashboard light
- Check engine light (MIL)
- Check-engine blink code
- —
- Applies to
- Generic OBD-II meaning. Not every code is used by this car.
- Description
- ECM/PCM Power Relay Control Circuit/Open
- Detection / symptoms
- 1.Check engine light on
- Possible causes
- 1.Potential causes for this code to set are 2.A defective PCM power relay 3.A blown fuse or fusible link 4.Corroded or damaged wiring or wiring connectors (especially near the PCM relay) 5.Faulty ignition switch 6.Partially or totally disconnected electrical terminal at the ignition switch 7.Loose or corroded battery cable ends
- What to check
- 1.Check all battery and ECM power and earth connections first 2.Read every stored code; an ECM fault is rare, wiring faults are common 3.Have a specialist confirm before replacing the ECM
- Confidence
- medium (generic OBD-II definition, not checked against the factory manual for this car)
Generic OBD-II meaning (obd-codes.com), not checked against this car's factory manual. Clear the code and test-drive to confirm it returns. Search all fault codes · Common problems · Warning lights