Theory Of Operation

The purpose of the diagnostic is to check if the service Electronic Shift Module (ESM) has been programmed by the dealer service technician with production software. The service ESM is received at the dealer service location with the program state bit set as "not programmed" in the ESM non-volatile memory. This bit will switch to the "programmed" state when the production software is programmed into the ESM. If this service procedure is not performed, a fault code will be set when the ESM is powered