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Principles of Operation




Horn

Principles of Operation

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

The Battery Junction Box (BJB) supplies the switched and control voltage to the horn relay (part of the SJB). When the horn switches are pressed, ground is supplied to the horn relay through the clockspring. The horn relay is then energized, directing voltage to the horn. When the perimeter anti-theft system is armed, the SJB can also provide ground to the horn relay coil to sound the horn, when the panic button is pressed on the Remote Keyless Entry (RKE) transmitter, or to indicate a programming feature sequence.