OBD-II code · Powertrain (generic)
P0690 ECM or PCM Power Relay Sense Circuit High
Same as P0689 with the sense line shorted to supply or showing higher voltage than expected. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Is it safe to drive with P0690?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySense line shorted to supply
- Less likelyConnector pins corroded - high contact resistance
- Less likelySupply wire pinched against B+ source
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
- Often, with basic tools
- Typical labour
- 0.5–1.8 h
- Emissions test
- Usually unaffected
- Parts involved
- Ecm Power Relay
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.