Description And Operation: Operation
The ESM communicates with the Transmission Control Module (TCM) and other modules on the CAN C bus. There is also a CAN EPT bus that is used only by the ESM and TCM. If one CAN bus is faulted, the other CAN bus transmits and receives the information required for uninterrupted operation.
The ESM can set Diagnostic Trouble Codes (DTCs) when a fault is detected. The ESM backlight can also indicate a fault by flashing the gear selection indicator ON and OFF or turning it off completely.
The ESM offers (P, R, N, D, L) modes of function.
The Electronic Park Brake Switch is the only separately serviceable part of the ESM.