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Fog/Driving Lamp: Description and Operation




FOG LAMPS

Principles of Operation


NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).
The SJB monitors the main light switch position by sending a voltage reference signal to the main light switch. When the fog lamp switch is engaged, the voltage reference signal is routed to ground.The fog lamps can be turned on when the following conditions are met:

- The ignition switch is in the RUN or START position.
- The low beam headlamps or the parking lamps are on.
- The high beams are off.When the SJB receives an input from the main light switch indicating a request for the fog lamps, the SJB provides ground to the fog lamp relay. When the fog lamp relay is energized, voltage is routed to the fog lamps.