Dodge Nitro. Manual — part 637

features function of the EMIC.

HEADLAMP LEVELING

In certain markets where required, a headlamp leveling system is provided on the vehicle. The headlamp
leveling system includes unique front headlamp units each connected to a headlamp leveling actuator motor,
and a rocker-actuated headlamp leveling switch integral to the switch pod in the instrument panel center stack.
The headlamp leveling system allows the headlamp beams to be adjusted to one of four vertical positions to
compensate for changes in inclination caused by the loading of the vehicle suspension. The leveling motors are
mechanically connected through an integral pushrod to the adjustable headlamp mounting collar.

Each time the headlamp leveling switch is depressed the circuitry of the switch pod provides an electronic
select status up or select status down message input to the EMIC over the LIN data bus. The EMIC then sends
the appropriate electronic select request up or select request down messages to the TIPM over the CAN data
bus. The TIPM responds to these messages by providing a voltage output to the headlamp leveling motors
through high side drivers on the headlamp leveling motor right and left signal circuits to move the headlamp
reflectors to the selected position based upon the voltage input received from the TIPM. The TIPM also sends
the appropriate electronic messages back to the EMIC and the EMIC relays the message back to the switch to
control the illumination of the 1 , 2 , or 3 Light Emitting Diode (LED) selected position indicator in the leveling
switch button. The EMIC and TIPM logic will only allow the headlamp leveling system to operate while the
ignition switch is in the ON position and the exterior lighting is turned ON.

PARK LAMPS

The park lamps system includes the left (lighting) multi-function switch, the SCM, the EMIC and the TIPM.
The front park/turn lamp and the position lamp bulbs each have a path to ground at all times through their
connection to the engine compartment wire harness. The engine compartment wire harness has takeouts with
eyelet terminals that are secured by nuts to ground studs on the front end sheet metal within the engine
compartment. The rear lamp units and license plate lamp bulbs have a path to ground at all times through a
takeout and eyelet terminal of the body wire harness that is secured by a nut to a ground stud on the body sheet
metal within the passenger compartment.

The SCM monitors a hard wired multiplex input from the left multi-function switch, then sends the appropriate
electronic headlamp switch status messages to the EMIC over the LIN data bus. Then the EMIC relays the
appropriate electronic message to the TIPM over the CAN data bus. The TIPM responds to these messages by
providing a battery voltage output to the appropriate lamp bulbs through high side drivers on the proper
park/tail/license/running lamp right and left circuits. The TIPM and the SCM also send the appropriate
electronic messages to the EMIC to control the illumination and lighting level of the panel lamps.

The TIPM provides a battery saver (load shedding) feature for the park lamps, which will turn these lamps OFF
if they are left ON for more than about eight minutes with the ignition switch in the LOCK position. The SCM
and the EMIC each provide a fail-safe feature for the park lamps, which will send an electronic message to the
TIPM to turn these lamps ON automatically if there is no input available from the left multi-function switch.
The TIPM also provides a fail-safe feature for the park lamps that will turn these lamps ON automatically
whenever a loss of CAN bus communication is detected with the ignition switch in the ON position.

REAR FOG LAMPS

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Lamps/Lighting - Exterior - Service Information - Nitro

Rear fog lamps are installed on vehicles manufactured for all export markets. The rear fog lamp system includes
the left (lighting) multi-function switch, the SCM, the EMIC and the TIPM. The rear fog lamp bulbs have a path
to ground at all times through a takeout and eyelet terminal of the body wire harness that is secured by a nut to a
ground stud on the body sheet metal within the passenger compartment.

The SCM monitors a hard wired multiplex input from the left multi-function switch to determine whether the
rear fog lamps are selected, then sends electronic rear fog lamp switch status messages to the EMIC over the
LIN data bus. Then the EMIC relays an electronic rear fog lamp request message to the TIPM over the CAN
data bus. The TIPM responds to this message by providing a battery voltage output to the rear fog lamp bulbs
through high side drivers on the fog lamp relay control rear circuit. The TIPM also sends the appropriate
electronic message back to the EMIC to control the rear fog lamp indicator.

The TIPM will automatically energize and de-energize the front fog lamps in concert with the rear fog lamps.
The TIPM also provides a battery saver (load shedding) feature for the rear fog lamps, which will turn these
lamps OFF if they are left ON for more than about eight minutes with the ignition switch in the LOCK position.

TRAILER TOW WIRING

Domestic market vehicles equipped with an optional trailer tow package include a trailer tow take out of the
body wire harness connected to a molded, seven-way trailer tow connector and an integral cover that are
snapped into a bracket on the trailer hitch receiver platform.

TURN SIGNAL LAMPS

The turn signal lamps system includes the left (lighting) multi-function switch, the SCM, the EMIC and the
TIPM. The front turn signal lamp bulbs each have a path to ground at all times through their connection to the
engine compartment wire harness. The engine compartment wire harness has a takeout with an eyelet terminal
that is secured by a nut to a ground stud on the body sheet metal within the engine compartment. The rear turn
signal lamp bulbs have a path to ground at all times through a takeout and eyelet terminal of the body wire
harness that is secured by a nut to a ground stud on the body sheet metal within the passenger compartment.

The SCM monitors a hard wired multiplex input from the left multi-function switch to determine the status of
the turn signal switch, then sends the appropriate electronic turn signal switch status messages to the EMIC
over the LIN data bus. Then the EMIC relays an electronic turn signal request message to the TIPM over the
CAN data bus. The TIPM responds to these messages by controlling a battery voltage output and the flash rate
for either the right or left turn signal lamps through high side drivers on the appropriate right or left turn signal
feed circuits. The TIPM also sends the appropriate electronic messages back to the EMIC to control the
illumination and flash rate of the right or left turn signal indicators, as well as to control the click rate of an
electromechanical relay soldered onto the EMIC electronic circuit board that emulates the sound emitted by a
conventional turn signal flasher.

The EMIC also provides a turn signal ON warning that will generate repetitive chimes to indicate that a turn
signal has been active continuously for 1.6 kilometers (1 mile) with the vehicle speed greater than 22
kilometers-per-hour (15 miles-per hour). Vehicles built for markets other than the United States and Canada
have a revised distance threshold of 4 kilometers (2.49 miles) for this feature. The chime will continue until the
turn signal input becomes inactive or until the vehicle speed message indicates that the speed is less than 22
kilometers-per-hour (15 miles-per-hour), whichever occurs first.

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Lamps/Lighting - Exterior - Service Information - Nitro

WARNING

LAMPS/LIGHTING - EXTERIOR

DIAGNOSIS AND TESTING

LAMPS/LIGHTING - EXTERIOR

The lamps and the hard wired circuits between components related to the exterior lighting system may be
diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out information and location views for the various wire harness

WARNING:

To avoid serious or fatal injury eye protection should be used when
servicing any glass components.

CAUTION: Do not contaminate the glass of halogen bulbs with fingerprints or allow

contact with other possibly oily surfaces. Reduced bulb life will result.

CAUTION: Do not use bulbs with higher candle power than indicated in the Bulb

Application table. See SPECIFICATIONS. In addition, do not use fuses,
circuit breakers or relays having greater amperage value than indicated on
the fuse panel or in the Owner's Manual. Damage to lamps, lenses, wiring
and other related electrical components can result.

WARNING:

To avoid serious or fatal injury on vehicles equipped with airbags, disable
the Supplemental Restraint System (SRS) before attempting any steering
wheel, steering column, airbag, Occupant Classification System (OCS),
seat belt tensioner, impact sensor, or instrument panel component
diagnosis or service. Disconnect and isolate the battery negative (ground)
cable, then wait two minutes for the system capacitor to discharge before
performing further diagnosis or service. This is the only sure way to
disable the SRS. Failure to take the proper precautions could result in
accidental airbag deployment.

NOTE:

When diagnosing the exterior lighting circuits, remember that high generator
output can burn out bulbs rapidly and repeatedly; and, that dim or flickering
bulbs can be caused by low generator output or poor battery condition. If one of
these symptoms is a problem on the vehicle, be certain to diagnose the battery
and charging system, then repair as necessary.

NOTE:

A good ground is necessary for proper lighting operation. If a lighting problem
is being diagnosed that involves multiple symptoms, systems, or components,
the problem can often be traced to a loose, corroded, or open ground.

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Lamps/Lighting - Exterior - Service Information - Nitro

connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the exterior lighting
system or the electronic controls or communication between modules and other devices that provide some
features of the exterior lighting system. The most reliable, efficient, and accurate means to diagnose the exterior
lighting system or the electronic controls and communication related to exterior lighting system operation
requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

BACKUP LAMPS

BRAKE LAMPS

CONDITION

POSSIBLE CAUSES

CORRECTION

BACKUP LAMP DOES NOT

ILLUMINATE

1. Ineffective or missing bulb. 1. Test and replace backup lamp bulb if

required.

2. Ineffective ground circuit.

2. Test and repair open backup lamp
ground circuit if required.

3. Ineffective feed circuit.

3. Test and repair open backup lamp feed
circuit if required.

4. Ineffective switch.

4. Test and replace backup lamp switch
(manual transmission) or transmission
range sensor (automatic transmission) if
required.

5. Ineffective TIPM inputs or
outputs.

5. Use a diagnostic scan tool to test the
TIPM inputs and outputs. Refer to the
appropriate diagnostic information.

BACKUP LAMP DOES NOT

EXTINGUISH

1. Ineffective feed circuit.

1. Test and repair shorted backup lamp
feed circuit if required.

2. Ineffective switch.

2. Test and replace backup lamp switch
(manual transmission) or transmission
range sensor (automatic transmission) if
required.

3. Ineffective TIPM inputs or
outputs.

3. Use a diagnostic scan tool to test the
TIPM inputs and outputs. Refer to the
appropriate diagnostic information.

NOTE:

The Center High Mounted Stop Lamp (CHMSL) is illuminated by several Light-
Emitting Diode (LED) units that are soldered to the electronic circuit board
within the lamp housing. The CHMSL is hard wired to the output of the brake
lamp switch, while the brake lamps are powered by high side drivers within the
TIPM based upon an input from the brake lamp switch. If the brake lamps and
all of the LED units within the CHMSL fail to operate, diagnose and repair the
brake lamps before attempting to repair the CHMSL. If the brake lamps operate
but none of the CHMSL LED units illuminate, test and repair the CHMSL ground
or feed circuit if required. If some of the CHMSL LED units operate and others
do not, the CHMSL assembly must be replaced with a new unit.

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Lamps/Lighting - Exterior - Service Information - Nitro