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Principles of Operation




Turn Signal and Hazard Lamps

Principles of Operation

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

The Smart Junction Box (SJB) monitors the multifunction switch position by sending voltage signals (for the LH and RH turn input) to the multifunction switch. When the multifunction switch is in the LH or RH TURN positions that input signal is switched to ground.

The SJB (Smart Junction Box) monitors the request for the hazard lamps by sending a voltage signal to the hazard flasher lamp switch. For MKZ, the hazard flasher lamp switch is integrated into the Front Controls Interface Module (FCIM).

When the SJB (Smart Junction Box) receives a request for a turn signal or hazard lamps, the SJB (Smart Junction Box) supplies voltage to the appropriate turn lamps.