The Transmission Control Module (TCM) is a computer that monitors the operation of the vehicle’s transmission. Depending on the manufacturer, it can be integrated into the Powertrain Control Module (PCM), as well as it can be standalone.
Like the various control modules, the TCM gets input signals from various sensors and switches. This information is used later on by the TCM to control various gear solenoid outputs and the Torque Converting Clutch (TCC) solenoid. It is only through the information provided by these devices that the TCM controls the operation of the transmission.
The DTC code P0882 OBD2 is set if the energy that is reaching the TCM is not enough. This code states that there is a short in the circuit.