Circuit Description

The transmission control module (TCM) provides the engine control module (ECM) vehicle speed information through the high-speed communications on the controller area network (CAN). Vehicle speed is produced by the AC current generated through the transmission output shaft speed (OSS) sensor as the output shaft rotates. The ECM continuously monitors the vehicle speed signal supplied by the TCM. If the ECM does not receive vehicle speed data from the TCM, this DTC sets.