Engine Control Module (ECM)
NOTE:
The remote control door lock receiver (RCDLR) does not communicate on the GM LAN high speed bus. The RCDLR and the ECM use the instrument panel module (IPM) as a gateway in order to communicate.
The ECM communicates with the IPM and the RCDLR over the serial data line. If the RCDLR receives a valid transmitter RF response, the RCDLR will send the fuel enable message to the ECM to enable the starting system. If the RCDLR does not receive a valid response from the transmitter, the RCDLR will send the fuel disable message, indicating to the ECM that vehicle starting should not be allowed. Additionally, if the fuel enable password received by the ECM does match the stored password, vehicle starting will be disabled.