What does it mean?
The transmission control relay (TCR) is used to supply power to the transmission solenoid pack during normal operation. When the relay is off, no power is supplied to the control pack and the transmission goes into “limp mode”. The relay is controlled by the powertrain control module (PCM) and/or transmission control module (TCM). Depending on the application, the TCR may be located in the intelligent power module (IPM), which is basically a smart fuse box, or in a standard fuse box. An example of a transmission control relay Code P0888 indicates the TCM has detected a problem with the transmission control relay and/or circuit.