Circuit/System Description

When the ignition is turned ON, the passenger presence system (PPS) and the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. The PPS is used to monitor the weight of an occupant in the front passenger seat. If the pressure from the occupant's weight is less than a specified value or an empty seat is detected, the PPS module will send a suppress signal to the SDM to disable the passenger side impact module (front seat air bag). When the PPS detects a fault within itself, then the PPS will communicate to the SDM through GMLAN communications that a PPS fault is present. The SDM will suppress the deployment of the module and then illuminate the AIR BAG indicator.