Diagnosis And Testing - Horn

Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin out information and location views for the various wire harness connectors, splices and grounds.

1. Disconnect the headlamp and dash wire harness connector from the connector on the right horn of the horn and mounting bracket unit. Check for continuity between the horn ground circuit pin in the headlamp and dash wire harness connector for the horns and a good ground. There should be continuity. If OK, go to Step 2. If not OK, repair the open ground circuit to ground as required.
2. Check for battery voltage at the horn circuit pin in the headlamp and dash wire harness connector for the horns. There should be zero volts. If OK, go to Step 3. If not OK, repair the shorted horn circuit between the horns and the Power Distribution Center (PDC) as required.
3. Depress the horn switch. There should now be battery voltage at the horn circuit pin of the headlamp and dash wire harness connector for the horns. If OK, replace the faulty horns and mounting bracket unit. If not OK, use a diagnostic scan tool and the appropriate diagnostic information for further diagnosis of the Body Control Module (BCM) (also known as the Common Body Controller/CBC), the Controller Area Network (CAN) data bus, the Local Interface Network (LIN) master node and CAN gateway of the Steering Angle Sensor (SAS) integral to the clockspring, the LIN slave node integral to the speed control switch pod, the LIN data bus and the horn switch.