P0887
TCM Power Relay Control Circuit High
Transmission / TCM power
Generic OBD-II
Medium
What it means
P0887 means a high-voltage fault on the control circuit for the transmission control module (TCM) power relay — the relay that feeds power to the transmission controller. The engine starts and runs, but if the TCM loses stable power the transmission can enter limp mode, shift harshly, or stick in one gear. Check the relay and its control wiring first.
Medium
Can I keep driving? The engine runs, but the transmission may lose power to its controller and enter limp mode or fail to shift — get it diagnosed soon.
Common symptoms
What you'll notice
- Check-engine light on
- Transmission won't shift or is stuck in one gear
- Harsh or unpredictable shifting
- Reduced power / limp-mode behaviour
Common causes
Most likely first
- Failed TCM power relayLikely
- Open or short-to-power in the relay control circuitCommon
- Loose or corroded connections at the relay or TCMCommon
- Failed control module driver (rare — check wiring and relay first)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for related TCM power codes.
- Inspect the TCM power relay and its socket/connector for corrosion or looseness.
- Test the relay and its control circuit for an open or short-to-power.
- Replace the relay if it fails to actuate; repair wiring, and consider the module only if the driver circuit is confirmed bad. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0887?+
Only short-term. If the TCM loses power it can force limp mode or leave you stuck in one gear. Have it checked before longer drives.
Can I just clear P0887?+
It returns until the relay or its control circuit is repaired. Clearing does not restore stable TCM power.
Related codes
Often seen with P0887
Read & clear P0887 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX