Theory Of Operation

When the Horn Switch is activated, the Body Control Module (BCM) receives a hardwired input signal from the Horn Switch, which passes through the Steering Column Control Module (SCCM), indicating that Horn operation is requested. The BCM provides a ground path to the coil side of the Horn Relay, located in the Power Distribution Center (PDC) Assembly, through the Horn Relay Control circuit and energizes the Horn Relay. When the Horn Relay is energized, voltage is supplied through the Fused Horn Control Output circuits to the Horn. The Horn ground circuits are attached to the body.