Chevrolet Equinox Service Manual: Horns System Description and Operation Horn

System Description

The horn system consists of the following components:

HORN fuseUnderhood fuse block (contains PCB horn relay)Horn switchHorn-low noteHorn-high noteBody control module (BCM)K84Keyless Entry Control ModuleS33Horn SwitchK73Telematics Communication Interface Control ModuleK9Body Control ModuleX50AFuse Block - UnderhoodP12AHorn - High NoteP12BHorn - Low Note

System Operation

The vehicle horn system is activated under the following conditions:

When the horn switch is depressedThe BCM commands the horns ON under any of the following conditions:When the content theft deterrent system detects a vehicle intrusion—For further informationrefer toTheft Systems Description and Operation.When the panic button is depressed on the remote control door lock transmitter—Forfurther information refer toKeyless Entry System Description and Operation.When the keyless entry system is used to lock the vehicle, a horn chirp may soundto notify the driver that the vehicle has been locked. The notification feature maybe enabled or disabled through personalization. For further information refer toKeyless Entry System Description and Operation.When the OnStar® system is used to sound the horns if equipped—For further information,refer toOnStar Description and Operation.Circuit Operation

Battery positive voltage is applied at all times to the horn relay coil and the hornrelay switch. Pressing either of the horn switches applies ground to the horn relaycontrol circuit. The BCM may also apply ground to the horn relay control circuit asdescribed above. When the horn relay control circuit is grounded, the horn relay isenergized and battery positive voltage is applied to the horns through the horn controlcircuit. Thehorns sound as long as ground is applied to the horn relay control circuit.