Principles Of Operation

Horn

Principles of Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

The SJB (Smart Junction Box) supplies the switched and control voltage to the horn relay (part of the SJB (Smart Junction Box)). When the horn switch is pressed, ground is supplied to the SJB (Smart Junction Box) through the clockspring. The SJB (Smart Junction Box) then energizes the horn relay sending voltage to the horn, enabling the horn to sound.

The horn switch is part of the driver air bag module. There are 2 sets of contacts on the air bag module that are separated by springs. One set of contacts is connected to ground and the other set is connected to the horn signal circuit. When the driver air bag module is depressed, the springs collapse allowing the contacts to touch, completing the circuit.

The SJB (Smart Junction Box) provides a momentary ground to the horn relay when the anti-theft system is armed, and an on then off ground when the PANIC button is pressed on the Remote Keyless Entry (RKE) key fob.