REAR FOG LAMP SWITCH
DESCRIPTION
The rear fog lamp switch (2) is used only on vehicles manufactured for certain markets where the rear fog lamps are available and also equipped with the optional automatic headlamp system. The rear fog lamp switch is integral to the upper switch pod (1) on the instrument panel. Only the switch push button is visible on the outer surface of the switch pod.
The black, molded plastic switch pod housing encloses the switch push button mechanism and the switch circuitry including the switch contacts. A connector receptacle is integral to the back of the switch pod housing. The switch is connected to the vehicle electrical system through a dedicated take out and connector of the instrument panel wire harness.
The rear fog lamp switch cannot be adjusted or repaired and, if ineffective or damaged, the entire upper switch pod unit must be replaced. (Refer to 8 - ELECTRICAL/INSTRUMENT CLUSTER/INSTRUMENT PANEL SWITCH POD - REMOVAL - UPPER).
OPERATION
The rear fog lamp switch receives a clean ground input from the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Control Node/CCN) at all times through the instrument panel wire harness. The only output from the switch is a momentary ground signal that the EMIC/CCN reads through an internal pull-up on a rear fog lamp switch output circuit.
The rear fog lamp switch as well as the hard wired inputs and outputs of the switch may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information.