P0886
TCM Power Relay Control Circuit Low
Transmission
Generic OBD-II
High
What it means
P0886 means the control circuit for the transmission control module's (TCM) power relay is reading low. That relay supplies power the TCM needs to run the transmission, so a fault here can leave the gearbox in limp mode or unable to move. The engine itself still starts. It usually points to a bad relay, a short in the control wiring, or a poor connection.
High
Can I keep driving? Risky — if the TCM loses power the transmission can drop into limp mode or fail to move; don't drive far until it's fixed.
Common symptoms
What you'll notice
- Check-engine light on
- Transmission stuck in limp mode or won't shift
- Vehicle may not move properly, or at all
- Reduced power or acceleration
Common causes
Most likely first
- Faulty TCM power relayLikely
- Wiring fault or short-to-ground on the relay control circuitCommon
- Loose or corroded electrical connectionsCommon
- Faulty control module driving the relay (TCM/ECM)Less often
How to diagnose & fix
Work through it in order
- Inspect the TCM power relay and its socket for damage; swap with a known-good identical relay to test.
- Check the relay control wiring for a short-to-ground or open causing the low signal.
- Clean and tighten grounds and connectors in the relay circuit.
- Verify the relay coil gets a proper control signal from the module.
- Replace the relay if it fails testing; address the control module only if wiring and relay check good. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0886?+
No — if the TCM loses power the transmission can enter limp mode or stop moving unexpectedly. Have it fixed before driving far.
Can I just clear P0886?+
It returns until the relay, its wiring, or the control circuit is repaired.
Related codes
Often seen with P0886
Read & clear P0886 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