Circuit Description

The engine control module (ECM) sends accelerator pedal position data to the transmission control module (TCM). The TCM uses this data to modify shift speeds. The data is sent to the TCM through a communication network, called the controller area network (CAN). Two circuits are used to communicate CAN data between the ECM and TCM. A fault in the CAN will not cause DTC P0120 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P0120.

When the TCM receives invalid accelerator pedal data from the ECM, DTC P0120 sets. DTC P0120 is a type A DTC.