P0888
TCM Power Relay Sense Circuit
- Severity
- High
- Driving
- Drive only to a garage
A fault in the power relay sense circuit. This is the wire the module uses to check whether the relay actually did what it was told - a feedback line rather than a control line. The module commanded the relay and cannot confirm the result, so it will not trust its own power supply.
Possible causes
- CommonFailed power relay with worn or stuck contacts
- CommonCorroded relay socket
- CommonWiring fault on the sense circuit
- PossibleWater ingress into the fuse box
- RareFailed module input
What you might notice
- Transmission in limp mode
- Intermittent loss of transmission function
- Battery draining after standing
- Check engine light on
What to check, in order
- Swap the relay with an identical one and see whether the fault follows.
- Inspect the relay socket for corrosion and heat damage.
- Check continuity on the sense wire between the relay and the module.
- Check the fuse box for water.
- Read the other relay codes stored. Control and sense codes together usually mean the relay itself.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Transmission
P0800P0801P0802P0803P0804P0805P0806P0807P0808P0809P0810P0811P0812P0813P0814P0815P0816P0817P0818P0819P0820P0821P0822P0823P0824P0825P0826P0827P0828P0829P0830P0831P0832P0833P0834P0835P0836P0837P0838P0839P0840P0841P0842P0843P0844P0845P0846P0847P0848P0849P0850P0851P0852P0853P0854P0855P0856P0857P0858P0859P0860P0861P0862P0863P0864P0865P0866P0867P0868P0869P0870P0871P0872P0873P0874P0875P0876P0877P0878P0879P0880P0881P0882P0883P0884P0885P0886P0887P0888P0889P0890P0891P0892P0893P0894P0895P0896P0897P0898P0899