Principles Of Operation

PRINCIPLES OF OPERATION

NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).

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

The horn switch is comprised of the steering wheel and the air bag. They are separated by springs and both have 3 contacts. The steering wheel is the ground and the air bag has a single wire lead. When the driver air bag module is depressed, the springs collapse allowing the contacts to touch, completing the circuit.

The SJB 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.