
Symptom:
CHECKING THE RAIN SENSOR/WIPER OPERATION
POSSIBLE CAUSES
CHECK THE WIPER MOTOR CIRCUIT CAVITY 2
CHECK THE WIPER MOTOR CIRCUIT CAVITY 5
CHECK THE WIPER MOTOR CIRCUIT CAVITY 5 II
CHECK THE WIPER MOTOR CIRCUIT CAVITY 6
CHECK THE WIPER MOTOR CIRCUIT CAVITY 6 II
CHECK WIPER MOTOR GROUND CIRCUIT
CHECKING THE 12 VOLT POWER SUPPLY
CHECKING THE GROUND CIRCUIT
CHECKING THE RAIN SENSOR OPERATION
CHECKING WIPER SIGNALS TO THE RAIN SENSOR MODULE
RAIN SENSOR
RAIN SENSOR CIRCUIT(S) OPEN
RAIN SENSOR CIRCUIT(S) SHORTED TO GROUND
RAIN SENSOR CIRCUIT(S) SHORTED TO VOLTAGE
RAIN SENSOR MODULE
RAIN SNSR CKTS SHORTED TOGETHER
WIPER MOTOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
Monitor the windshield wipers while turning the wiper switch to each of the 4 switch
positions: OFF, INTERMITTENT, LOW and HIGH.
Did the wipers functions properly in each wiper switch position?All
Ye s!Go To 2
No!Go To 8
2NOTE: The Rain Sensor is located in the windshield mount of the rear view
mirror in the top-center of the windshield.
NOTE: The Rain Sensor Module (RSM) is mounted above the accelerator
pedal assembly.
Turn the ignition on.
Move the Wiper Switch to the Intermittent position.
Spray or pour water on the Rain Sensor area of the windshield.
Did the wipers activate when water was sprayed/poured on the Rain Sensor area of
the windshield?All
Ye s!Rain Sensor/Wiper System operating properly. Test complete.
No!Go To 3
239
WINDSHIELD WIPER & WASHER

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Rain Sensor Module harness connector.
Measure the resistance between ground and each of the Rain Sensor circuits at the
Rain Sensor Module harness connector.
Is the resistance above 1000 ohms for each measurement?All
Ye s!Go To 4
No!Repair the circuit(s) that measured below 1000 ohms for a short to
ground.
4 Turn the ignition off.
Disconnect the Rain Sensor Module harness connector.
Turn the ignition on.
Measure the voltage of each of the Rain Sensor circuits at the Rain Sensor Module
harness connector.
Is the voltage below 1.0 volt for each measurement?All
Ye s!Go To 5
No!Repair the circuit(s) that measured above 1.0 volt for a short to
voltage.
5 Turn the ignition off.
Disconnect the Rain Sensor harness connector.
Disconnect the Rain Sensor Module harness connector.
Measure the resistance of each Rain Sensor circuit between the Rain Sensor Module
harness connector and the Rain Sensor harness connector.
Is the resistance below 10.0 ohms for each measurement?All
Ye s!Go To 6
No!Repair the circuit(s) that measured above 10.0 ohms for an open.
6 Turn the ignition off.
Disconnect the Rain Sensor harness connector.
Disconnect the Rain Sensor Module harness connector.
Measure the resistance between Rain Sensor harness connector cavities 1 and 2.
Repeat this step for cavities 1 and 3, cavities 2 and 3.
Is the resistance above 1000 ohms for each measurement?All
Ye s!Go To 7
No!Repair the circuit(s) that measured below 1000 ohms for a short
together.
7 Turn the ignition off.
Replace the Rain Sensor in accordance with the Service Information.
Turn the ignition on.
Move the Wiper Switch to the Intermittent position.
Spray or pour water on the Rain Sensor area of the windshield.
NOTE: The Rain Sensor is located in the windshield mount of the rear view
mirror in the top-center of the windshield.
Did the wipers activate when water was sprayed/poured on the Rain Sensor area of
the windshield?All
Ye s!Replace the original Rain Sensor in accordance with the Service
Information.
No!Replace the Rain Sensor Module in accordance with the Service
Information.
240
WINDSHIELD WIPER & WASHER
CHECKING THE RAIN SENSOR/WIPER OPERATION ÐContinued

GROUP TAB LOCATOR
Introduction
0Lubrication & Maintenance
2Suspension
3Differential & Driveline
5Brakes
7Cooling
8AAudio/Video
8BChime/Buzzer
8EElectronic Control Modules
8FEngine Systems
8GHeated Systems
8HHorn
8IIgnition Control
8JInstrument Cluster
8LLamps
8NPower Systems
8ORestraints
8PSpeed Control
8QVehicle Theft Security
8RWipers/Washers
8WWiring
9Engine
11Exhaust System
13Frame & Bumpers
14Fuel System
19Steering
21Transmission
22Tires/Wheels
23Body
24Heating & Air Conditioning
25Emissions Control
Component and System Index
Service Manual Comment Forms (Rear of Manual)

SCOPE OF WORK FOR MAINTENANCE SERVICE
Oil Service
²Engine: Oil change and filter replacement
Check fluid levels of the following system, refill as neces-
sary.
²If fluid is lost, trace and eliminate cause - as a
separate order.
²Power-assisted steering
Lubrication work:
²Trailer tow hitch (original equipment)
Maintenance
²ASSYST maintenance computer reset
Function check
²Signalling system, warning and indicator lamps
²Headlamps, exterior lighting
²Windshield wipers, windshield washer system
Check for leaks and damage
²Check for abrasion points and ensure that lines
are correctly routed!
²All lines and hoses, sensor cables
²Rubber boots on front axle drive shafts, rubber
boots on front axle suspension ball joints, shock
absorbers
²Check fluid levels for the following systems, cor-
rect as necessary
NOTE: Should there be a loss of fluid which cannot
be explained by regular use, trace and eliminate the
cause.
²Engine cooling system. Check corrosion inhibi-
tor/antifreeze, refill as necessary.
²Hydraulic brake system
²Battery
²Windshield washer system
Engine
²Fuel filter renewal - Every oil service
²Air cleaner with maintenance indicator:
²Check degree of contamination.
²Air cleaner filter element renewed as necessary.
Chassis and body
²Trailer coupling: Check operation, play and
retaining fixtures
²Secondary rubber springs: Visual check
²Tire pressures: Correct as necessary, including
spare tire
²Check thickness of brake pads
²Brake test
²Check condition of steering mechanism
²Heating/ventilation dust filter renewal
ADDITIONAL MAINTENANCE WORK
Automatic transmission once only at 80,000 miles / 128000
km
²Oil and filter change
During every second maintenance service
²Air cleaner without maintenance indicator:
²Air cleaner filter element renewal
²Check poly-V-belt for wear and signs of damage
During every fourth maintenance service
²Change rear axle fluid
ADDITIONAL MAINTENANCE WORK AFTER YEARS
Every 2 years
²Change brake fluid.
Every 3 years
²Air cleaner filter element renewal (note installa-
tion date)
Every 15 years or 100,000 miles
²Coolant renewal
²Note coolant composition
INTERNATIONAL SYMBOLS
DESCRIPTION
DaimlerChrysler Corporation uses international
symbols to identify engine compartment lubricant
and fluid inspection and fill locations (Fig. 3).
Fig. 3 INTERNATIONAL SYMBOLS
VALUBRICATION & MAINTENANCE 0 - 9

the left and right turn signal circuits. Each turn sig-
nal indicator Light Emitting Diode (LED) is com-
pletely controlled by the instrument cluster logic
circuit, and that logic will allow this indicator to
operate whenever the instrument cluster receives a
battery current input on the fused B(+) circuit.
Therefore, each LED can be illuminated regardless of
the ignition switch position. The LED only illumi-
nates when it is provided a path to ground by the
instrument cluster transistor. The instrument cluster
will turn on the turn signal indicators for the follow-
ing reasons:
²Turn Signal Input- Each time the cluster
detects a turn signal input from the turn signal relay
through the closed turn signal switch circuitry of the
multi-function switch on the hard wired left or right
turn signal circuit, the requested turn signal lamps
and turn signal indicator will be flashed on and off,
and a contactless relay soldered onto the cluster elec-
tronic circuit board will produce a clicking sound to
emulate a conventional turn signal flasher. The turn
signals and the turn signal indicators continue to
flash on and off until the turn signal switch circuitry
of the multi-function switch is opened, or until the
ignition switch is turned to the Off position, which-
ever occurs first.
²Hazard Warning Input- Each time the cluster
detects a hazard warning input from the turn signal
relay through the closed hazard warning switch cir-
cuitry of the multi-function switch on the hard wired
left and right turn signal circuits, all of the turn sig-
nal lamps and both turn signal indicators will be
flashed on and off, and a contactless relay soldered
onto the cluster electronic circuit board will produce
a clicking sound to emulate a conventional hazard
warning flasher. The turn signals and the turn signal
indicators continue to flash on and off until the haz-
ard warning switch circuitry of the multi-function
switch is opened.
An electronic wipers, turn signals and engine start
control module located within the fuse block beneath
the steering column monitors the turn signal circuits
and controls the flash rate of the turn signal relay.
The instrument cluster continually monitors the
right and left turn signal circuits to determine the
proper turn signal and hazard warning indicator
operation, then flashes the proper turn signal indica-
tors and the contactless relay on and off accordingly.
The multi-function switch, the turn signal relay and
the left and right turn signal circuits to the instru-
ment cluster can be diagnosed using conventional
diagnostic tools and methods. For proper diagnosis of
the wipers, turn signals and engine start control
module within the fuse block or the instrument clus-
ter circuitry that controls the turn signal indicators
and the contactless relay, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.WAIT - TO - START INDICATOR
DESCRIPTION
A wait-to-start indicator is standard equipment in
all instrument clusters. The wait-to-start indicator is
located near the lower edge of the instrument cluster,
to the right of the multi-function indicator display.
The wait-to-start indicator consists of the Interna-
tional Control and Display Symbol icon for ªDiesel
Preheatº imprinted within a rectangular cutout in
the opaque layer of the instrument cluster overlay.
The dark outer layer of the overlay prevents the indi-
cator from being clearly visible when it is not illumi-
nated. An amber Light Emitting Diode (LED) behind
the cutout in the opaque layer of the overlay causes
the icon to appear silhouetted against an amber field
through the translucent outer layer of the overlay
when the indicator is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. The wait-to-start indicator is
serviced as a unit with the instrument cluster.
OPERATION
The wait-to-start indicator gives an indication to
the vehicle operator when the diesel engine glow
plugs are energized in their pre-heat operating mode.
This indicator is controlled by a transistor on the
instrument cluster circuit board based upon cluster
programming and electronic messages received by
the cluster from the Engine Control Module (ECM)
over the Controller Area Network (CAN) data bus.
The wait-to-start indicator Light Emitting Diode
(LED) is completely controlled by the instrument
cluster logic circuit, and that logic will only allow
this indicator to operate when the instrument cluster
detects that the ignition switch is in the On position.
Therefore, the LED will always be off when the igni-
tion switch is in any position except On. The LED
only illuminates when it is provided a path to ground
by the instrument cluster transistor. The instrument
cluster will turn on the wait-to-start indicator for the
following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the wait-to-start indicator
is illuminated for about two seconds as a bulb test.
²Wait-To-Start Lamp-On Message- Each time
the cluster receives a wait-to-start lamp-on message
from the ECM indicating that the diesel engine glow
plugs are energized in their pre-heat operating mode,
the wait-to-start indicator will be illuminated. The
indicator remains illuminated until the cluster
receives a wait-to-start lamp-off message indicating
that the pre-heat mode of the glow plugs has been
completed, until the ECM detects that the engine is
running, or until the ignition switch is turned to the
Off position, whichever occurs first.
8J - 28 INSTRUMENT CLUSTERVA

electrical package have a heavy duty 7-way trailer
tow connector installed in a bracket on the trailer
hitch receiver. This package includes a 7-way to
4-way connector adapter unit.
²Trailer Tow Control Module- Vehicles
equipped with a factory-approved, field-installed
trailer towing electrical package have a trailer tow
brake/turn control module located within the driver
side front seat riser that controls the brake lamp and
turn signal lamp outputs to the trailer lighting cir-
cuits.
²Turn Signal Relay- A turn signal relay is
installed in the fuse block located on the underside of
the steering column behind a fuse access panel in the
steering column opening cover on the instrument
panel. The electronic circuitry of the wipers, turn sig-
nals and engine start control module within the fuse
block controls the turn signal relay.
²Wipers, Turn Signals, Engine Start Control
Module- The wipers, turn signals and engine start
control module is integral to the fuse block located on
the underside of the steering column behind a fuse
access panel in the steering column opening cover on
the instrument panel. This module includes active
electronic elements that control the operation of the
turn signal relay based upon inputs from the multi-
function switch and feedback from the turn signal
circuits. (Refer to 8 - ELECTRICAL/POWER DISTRI-
BUTION/FUSE BLOCK - DESCRIPTION).
Hard wired circuitry connects the exterior lighting
system components to the electrical system of the
vehicle. These hard wired circuits are integral to sev-
eral wire harnesses, which are routed throughout the
vehicle and retained by many different methods.
These circuits may be connected to each other, to the
vehicle electrical system and to the exterior lighting
system components through the use of a combination
of soldered splices, splice block connectors, and many
different types of wire harness terminal connectors
and insulators. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
OPERATION
Following are paragraphs that briefly describe the
operation of each of the major exterior lighting sys-
tems. The hard wired circuits and components of the
exterior lighting systems may be diagnosed and
tested using conventional diagnostic tools and proce-
dures. However, conventional diagnostic methods
may not prove conclusive in the diagnosis of the wip-
ers, turn signals and engine start control module
located within the fuse block underneath the steering
column, the ElectroMechanical Instrument Cluster
(EMIC), the Engine Control Module (ECM), or theController Area Network (CAN) data bus network.
The most reliable, efficient, and accurate means to
diagnose the electronic module within the fuse block,
the EMIC, the ECM, and the CAN data bus network
inputs and outputs related to the various exterior
lighting systems requires the use of a diagnostic scan
tool. Refer to the appropriate diagnostic information.
BACKUP LAMPS
The backup (or reverse) lamps have a path to
ground received at all times through the vehicle wire
harness from a ground point located on the frame
near the left end of the tailgate sill. The backup
lamps receive battery current on the backup lamp
supply circuit only when the backup lamp switch cir-
cuit of the Transmission Range Sensor (TRS) integral
to the gear shifter assembly is closed by the gear
shifter mechanism.
BRAKE LAMPS
The brake (or stop) lamps have a path to ground at
all times through the vehicle wire harness from a
ground point located on the frame near the left end
of the tailgate sill. The Center High Mounted Stop
Lamp (CHMSL) has a path to ground at all times
through the vehicle wire harness from a ground point
on the left side of the dash panel. The brake lamps
and CHMSL receive battery current on the brake
lamp switch output circuit when the brake lamp
switch is closed by the brake pedal arm.
DAYTIME RUNNING LAMPS
Vehicles manufactured for sale in Canada illumi-
nate the low beam headlamp bulb when the engine is
running and the exterior lamps are turned off. This
feature is enabled by the right and left Daytime Run-
ning Lamps (DRL) relays. When the DRL relays are
de-energized, they provide fused battery current from
the circuit K26 relay to the headlamp low beams.
When the headlamps are turned On using the left
(lighting) control stalk of the multi-function switch
the DRL relays are energized, which returns control
of the headlamps to the headlamp switch circuitry of
the multi-function switch. The circuit K26 relay is
energized by the ElectroMechanical Instrument Clus-
ter (EMIC) whenever it receives an electronic mes-
sage from the Engine Control Module (ECM) over the
Controller Area Network (CAN) data bus indicating
that the engine is running. The DRL and circuit K26
relays are installed in a relay bracket located below
the forward edge of the driver side front seat cushion
within the driver side front seat riser.
FRONT FOG LAMPS
Vehicles equipped with optional front fog lamps
have a front fog lamp relay installed in a relay
bracket located below the forward edge of the driver
side front seat cushion within the driver side front
VALAMPS/LIGHTING - EXTERIOR 8L - 3

seat riser, a fog lamp switch installed in the cluster
bezel on the instrument panel outboard of the steer-
ing column, and a fog lamp bulb installed in each of
the two front lamp units. The front fog lamps have a
path to ground at all times through their connection
to the vehicle wire harness. The headlamp switch cir-
cuitry of the left (lighting) control stalk of the multi-
function switch controls front fog lamp operation by
providing battery current to the front fog lamp relay
only when the low beam headlamps are selected. The
fog lamp switch controls front fog lamp operation by
energizing or de-energizing the front fog lamp relay
control coil.
HAZARD WARNING LAMPS
With the hazard switch in the On position, the
hazard switch button illuminates and the right and
left turn signal indicators as well as the right and
left turn signal lamps begin to flash on and off. When
the hazard warning system is activated, the hazard
switch circuitry within the multi-function switch and
the wipers, turn signals and engine start control
module electronic circuitry within the fuse block will
repeatedly energize and de-energize the turn signal
relay located in the fuse block. The turn signal relay
switches battery current from a fused B(+) fuse in
the fuse block to the turn signal indicators and the
turn signal lamps. The flashing of the hazard switch
button illumination lamp is also controlled by the
output from the turn signal relay.
HEADLAMPS
The headlamp system includes the exterior lighting
switches integral to the left (lighting) control stalk of
the multi-function switch as well as the low and high
beam bulbs installed in the right and left front lamp
units (Fig. 1). The headlamp bulbs have a path to
ground at all times through the vehicle wire harness.
The exterior lighting switches control headlamp oper-
ation by providing battery current to the selected low
or high beam bulbs. Each front lamp unit includes
two integral adjustment screws to be used for static
horizontal and vertical aiming of the headlamp beam
reflectors.HEADLAMP LEVELING
The headlamp leveling system includes a leveling
actuator motor integral to each front lamp unit, and
a rotary thumbwheel actuated headlamp leveling
switch in the cluster bezel on the instrument panel
outboard of the steering column. The headlamp lev-
eling system allows the headlamp beam reflectors to
be adjusted to one of four vertical positions to com-
pensate for changes in inclination caused by the load-
ing of the vehicle suspension. The actuator motors
are mechanically connected through an integral
pushrod to an adjustable headlamp reflector. The
headlamp leveling switch is a resistor multiplexed
unit that provides one of four voltage outputs to the
headlamp leveling motors. The headlamp leveling
motors will move the headlamps to the selected posi-
tion based upon the voltage input received from the
switch. The headlamp leveling motors and switch
have a path to ground at all times. The headlamp
leveling components operate on battery current
received through the park lamps circuit so that the
system will only operate when the exterior lighting is
turned on.
PARK LAMPS
The park lamps system includes the exterior light-
ing switches integral to the left (lighting) control
stalk of the multi-function switch (Fig. 1), the front
park/side marker lamps, the front position lamps, the
rear park lamps, the rear side marker lamps, the
optional clearance lamps, and the license plate
lamps. Each of these lamps are provided with a path
to ground at all times through the vehicle wire har-
ness. The exterior lighting switches control the park
lamp operation by providing battery current through
the park lamps circuit to the appropriate lamp bulbs.
Fig. 1 Lighting Switch
1 - LEFT TURN SIGNAL
2 - RIGHT TURN SIGNAL
3 -EXTERIOR LIGHTING
4 - BEAM SELECT (DIMMER)
5 - OPTICAL HORN
8L - 4 LAMPS/LIGHTING - EXTERIORVA

TURN SIGNAL LAMPS
When the left (lighting) control stalk of the multi-
function switch is activated (Fig. 1), the turn signal
system illuminates the selected right or left turn sig-
nal indicator and the turn signal lamps begin to
flash. The turn signal lamps include a bulb integral
to each front lamp unit and each tail lamp unit, as
well as a repeater lamp bulb located on each front
fender above the front wheels. When the turn signal
system is activated, the turn signal switch circuitry
within the multi-function switch and the electronic
circuitry of the wipers, turn signals and engine start
control module within the fuse block will repeatedly
energize and de-energize the turn signal relay
located in the fuse block. The turn signal relay
switches battery current from a fused ignition switch
output fuse in the fuse block to the appropriate turn
signal indicator and turn signal lamps.
The ElectroMechanical Instrument Cluster (EMIC)
contactless relay will generate repetitive, audible
turn signal ªclickº sounds to emulate the sounds of a
conventional electro-mechanical turn signal flasher
at one of two rates to coincide with the flashing of
the turn signals. The slow rate emulates normal turn
signal operation, while the fast rate emulates ªbulb
outº turn signal operation.
SPECIFICATIONS - LAMPS / LIGHTING - EXTE-
RIOR
BULB SPECIFICATIONS
LAMP BULB
Backup P21W - 12V 21W
Brake & Rear Park P21/5W - 12V 21/5W
Center High Mounted
StopP21W - 12V 21W
Clearance W3W - 12V 3W
Front Fog H1 - 12V 55W
Front Position W5W - 12V 5W
Front Turn, Park & Side
Marker3457 NA - 12V 28/7.5W
Amber Glass
Low Beam Headlamp H7 - 12V 55W
High Beam Headlamp H1 - 12V 55W
License Plate C5W - 12V 5W
Rear Side Marker R5W - 12V 5W
Rear Turn P21W - 12V 21W
Side Repeater W5W - 12V 3W
BACKUP LAMP BULB
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) If the vehicle is so equipped, remove the trim
from the inside of the right or left rear corner pillar.
(3) From inside the vehicle, use hand pressure to
push the two latch tabs toward the center of the tail
lamp unit socket plate and pull the socket plate
straight out from the inner rear pillar (Fig. 2).
(4) Pull the socket plate away from the inner rear
pillar far enough to access the backup lamp bulb
(Fig. 3).
Fig. 2 Tail Lamp Socket Plate Remove/Install
1 - SOCKET PLATE
2 - INNER REAR PILLAR
3 - LATCH TAB (2)
VALAMPS/LIGHTING - EXTERIOR 8L - 5