Fail-safe Operation
WARNING: This page is about a different car, the 2006 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
The remote control door lock receiver (RCDLR) is the backup power mode master (BPMM). The both IPM and RCDLR receive signals from the ignition mode switch, representing the mode switch data, through 2 different circuits. The RCDLR can determine and transmit all the system power modes per the lists above. Since the operation of the vehicle systems depends on the power mode, there is a fail-safe plan in place if the power mode message is not received from the IPM or RCDLR. The fail-safe plan covers modules with discrete ignition signal inputs as well as those modules using exclusively serial data control of power mode. The ECM and TCM behave differently.