When the vehicle is turned on, the transmission control relay is responsible for powering the solenoids that operate the transmission. If there is a problem detected along its circuit, a P0888 DTC will be saved.
How Serious is the Code?
The P0888 diagnostic trouble code means that your transmission solenoids will not work, so the gearbox will default into limp mode to protect itself from further damage.
Symptoms of a P0888 include:
- Limp mode
- Transmission refuses to shift
- Damaged wiring or connectors
- Transmission control relay failure
- ECU or TCM programming problems
How to Diagnose the Code?
One of the first things that should be done when trying to diagnose a P0888 OBDII trouble code, is to check the operation of the transmission control relay with a volt meter. If it checks out, then check the wiring and connectors between the ECU and the transmission control relay.
What Repairs Will Fix P0888?
- Repair or replace damaged wiring and/or connectors
- Replace transmission control relay
- Update ECU or TCM software