OBD-II code · Powertrain (generic)
P0887 TCM Power Relay Control Circuit High
The TCM power relay reports a control circuit high condition. TCM supply control is impaired. 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 P0887?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyControl wire shorted to B+
- PossibleOpen relay coil
- Less likelyConnector pins corroded - high contact resistance
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Tcm Power Relay, Wiring Harness, Tcm
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.