the switch is damaged, the entire switch unit must be replaced. The clockspring (with the multi-function switch
mounting bracket), the left multi-function switch (with the SCM), the right multi-function switch and the
jumper wire harness are each available for separate service replacement.
OPERATION
LEFT MULTI- FUNCTION SWITCH
The left (lighting) multi-function switch uses resistor multiplexing to control the many functions and features it
provides using a minimal number of hard wired circuits. The switch receives clean grounds from the Steering
Control Module (SCM), then provides resistor multiplexed return outputs to the SCM to indicate the selected
switch positions. The SCM then sends electronic switch status messages over a Local Interface Network (LIN)
data bus to the Electro Mechanical Instrument Cluster (EMIC) (also known as the Cab Compartment
Node/CCN), and the EMIC relays electronic switch request messages over the Controller Area Network
(CAN) data bus to other electronic modules in the vehicle.
If the SCM detects no inputs from the left multi-function switch, it transmits an electronic Signal Not Available
(SNA) status message over the LIN data bus. The SNA status signals the EMIC to request other electronic
modules to implement a fail-safe mode of operation for the exterior lighting systems. The fail-safe mode
automatically turns the exterior lighting ON when the ignition switch is in the ON position, and OFF when the
ignition switch is in the OFF position.
The hard wired inputs and outputs of the left multi-function switch and SCM may be diagnosed using
conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, the most
reliable, efficient and accurate means to diagnose this component requires the use of a diagnostic scan tool.
Refer to the appropriate diagnostic information.
EXTERIOR LIGHTING
Following are descriptions of how the left multi-function switch is operated to control the many exterior
lighting functions and features it provides:
Front Fog Lamps - The optional front fog lamps are requested when the left multi-function switch
control knob is pulled outward to the front fog lamps detent position. The SCM reads the resistor
multiplexed input from the left multi-function switch and sends an electronic exterior lighting switch
status message over the LIN data bus to the EMIC, which relays an electronic exterior lighting switch
request message over the CAN data bus to other electronic modules in the vehicle. The switch control
knob incorporates an internal cam mechanism that will only allow the front fog lamps to be selected
while the headlamp ON position is also selected, and will automatically move the control knob to the
front fog lamps OFF position when the control knob is rotated to deselect the headlamps.
Headlamps - The headlamps are requested when the left multi-function switch control knob is rotated to
the headlamps ON detent position. The SCM reads the resistor multiplexed input from the left multi-
function switch and sends an electronic exterior lighting switch status message over the LIN data bus to
the EMIC, which relays an electronic exterior lighting switch request message over the CAN data bus
to other electronic modules in the vehicle.
Headlamp Beam Selection - The headlamp high beams are selected when the left multi-function switch
control stalk is pushed forward to the high beam selection detent position. The low beams are selected
2007 Dodge Nitro R/T
2007 ACCESSORIES AND EQUIPMENT Lamps/Lighting - Exterior - Service Information - Nitro