Circuit Description

The engine control module (ECM) sends engine coolant temperature data to the transmission control module (TCM). The TCM uses this data to initiate warm-up shift patterns and to establish default transmission fluid temperature (TFT) values. 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 P0115 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P0115.

When the TCM receives invalid engine coolant temperature data from the ECM, then DTC P0115 will set. DTC P0115 is a type C DTC.