OBD-II code · Powertrain (generic)
P0687 ECM/PCM Power Relay Sense Circuit Open
ECM/PCM Power Relay Sense Circuit Open: the circuit is open. Likely a broken wire, disconnected connector, or failed component.
Is it safe to drive with P0687?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyMain relay contacts faulty
- PossibleSense wire open
- Less likelyPin pushed back out of connector body
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.3–2 h
- Emissions test
- Likely to fail
- Parts involved
- Ecm, Main Relay
Related codes
- P0686ECM/PCM Power Relay Control Circuit Open
- P0688ECM/PCM Power Relay Sense Circuit High
- P0684Glow Plug Control Module 1 to PCM Communication Range or Performance
- P0685ECM or PCM Power Relay Control Circuit Open
- P0689ECM or PCM Power Relay Sense Circuit Low
- P068AECM or PCM Power Relay De-Energized Performance Too Early
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.