Twilight Sentinel

The twilight delay switch in the headlamp switch is supplied a reference voltage and a reference ground from the instrument panel integration module. The switch is a potentiometer that varies resistance as the switch is moved. The IPM receives an input voltage proportional to the resistance of the potentiometer via twilight delay input circuit. The IPM sends a class 2 message to the Dash Integration Module (DIM) indicating the on/off status and delay length for the twilight sentinel. With the twilight sentinel in an ON position, the DIM will automatically control the headlamps on/off status depending on the nighttime/daytime status of the ambient light sensor. The DIM will use the twilight sentinel delay length to know how long to keep the headlamps and park lamps on after the ignition switch transitions from ON to OFF during nighttime conditions.