Twilight Sentinel

The twilight sentinel system keeps the exterior lamps on for a pre-selected period of time after the ignition is turned off to improve night visibility when leaving the vehicle. The instrument cluster adjusts the twilight delay in 10 second intervals from 3 to 180 seconds in response to the voltage level at the twilight delay input. If the twilight sentinel is turned off during the delay period, the headlamps and the park lamps will turn off immediately. The lamps will be turned off automatically after the selected time period elapses from a few seconds to 3 minutes. The twilight delay switch in the headlamp switch assembly is supplied a 5 volt reference from the Instrument Cluster (IPC). The IPC also provides ground to the twilight delay switch. The switch is a potentiometer in which the resistance varies as the switch is moved. The IPC receives an input voltage proportional to the resistance of the potentiometer through the twilight delay signal circuit. The IPC sends a class 2 message to the BCM indicating the on/off status and delay length for the twilight sentinel. With the twilight sentinel switch in any position other than OFF, the BCM will turn the headlamps on or off according to the daytime/nighttime status sent by the IPC. The BCM uses the twilight delay signal in order to keep the headlamps and park lamps on after the ignition switch transitions from ON to OFF during nighttime conditions.