3.10 Communications Network Monitors

3.10 Communications Network Monitors
3.10.1 Description
The TCM communicates with the engine control module and ABS system via a controller area network (CAN). All control modules connected to the network continually monitor it for correct operation. The TCM monitors the following functions:

1. Incorrect configuration identifier received. The CAN configuration identifier received by the TCM does not match the one stored in its internal memory.
2. TCM CAN driver detects CAN bus error. The CAN control hardware/software within the TCM detects a network error causing the data transmitted and received to be corrupted.
3. CAN timeout. Messages have not been received form the ECM for longer than the defined time. All control modules connected to the CAN network transmit regular messages to confirm that they are still active.
4. Engine torque signal inaccurate. The engine torque signal is transmitted by the ECM, if the value transmitted is implausible then the TCM will register a network failure.
5. Engine speed signal too high. If the engine speed transmitted by the ECM exceeds 7100 rpm for longer than 2.55 seconds then a failure is registered.








If the above table does not include details of the following enabling conditions: - IAT, ECT, vehicle speed range, and time after engine start-up then the state of these parameters has no influence upon the execution of the monitor.