Theory Of Operation
When the Body Control Module (BCM) receives a hardwired input from the Headlamp Switch, requesting Park Lamp illumination, the BCM provides a voltage output through the Front Side Marker Lamp Control and Rear Side Marker Lamp Control circuits to the Front and Rear Sidemarker Lamps. A ground path for the Front and Rear Sidemarker Lamps is present through the wiring harness to the body sheet metal.