Horn: Description and Operation

Circuit Operation
Voltage is applied at all times through the HORN fuse to the horn relay in the underhood fuse block. The circuit continues from the horn relay to the horn switch. When the horn switch is closed, the circuit path is completed to ground and the horn relay energizes. The BCM may also apply ground to the horn relay control circuit when the content theft deterrent system detects a vehicle intrusion, when the panic button is depressed on the remote control door lock transmitter, when the lock button on the keyless entry transmitter is pressed twice within 5 seconds, a horn chirp will sound to notify the driver that the vehicle has been locked, or when the OnStar system is used to sound the horns (if equipped). The relay contact closes and battery voltage is applied to the horn. The horn sounds.