2003 JEEP GRAND CHEROKEE Electronic

the more frequently the RSM will send wipe com-
mands to the BCM to operate the front wiper system.
The RSM operates on battery current received
through a fuse in the Junction Block (JB) on a fused
B(+) circuit. This circuit is switched by the power
accessory (sunroof) delay relay in the JB so that the
RSM will operate whenever the relay is energized by
the BCM. The RSM receives ground at all times
through a take out of the left body wire harness with
an eyelet terminal that is secured by a ground screw
to the front seat crossmember on the floor panel
under the left front seat. It is important to note that
the default condition for the wiper system is auto-
matic wipers Off; therefore, if no message is received
from the RSM by the BCM for more than about five
seconds, the automatic wipers will be disabled and
the BCM will default the front wiper system opera-
tion to the low speed continuous wipe mode.
The RSM ground and battery current inputs can be
diagnosed using conventional diagnostic tools and
methods. However, conventional diagnostic methods
may not prove conclusive in the diagnosis of the RSM
internal circuitry, the BCM, the PCI data bus net-
work, or the electronic messages received and trans-
mitted by the RSM over the PCI data bus. The most
reliable, efficient, and accurate means to diagnose
the RSM requires the use of a DRBIIItscan tool.
Refer to the appropriate diagnostic information.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SIDE CURTAIN AIRBAG,
FRONT IMPACT SENSOR, SIDE IMPACT SENSOR,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Adjust the inside rear view mirror on the wind-
shield downward far enough to access the lower edge
of the Rain Sensor Module (RSM) trim cover (Fig.
15).
(3) Using a small thin-bladed screwdriver inserted
into the notch at the bottom of trim cover, gently prythe trim cover away from the windshield glass until
it unsnaps from the RSM.
(4) Using a small thin-bladed screwdriver, gently
pry the spring clips on each side of the RSM away
from the bracket on the windshield.
(5) Pull the RSM away from the bracket on the
windshield far enough to access and disconnect the
overhead wire harness connector for the module from
the module connector receptacle.
(6) Remove the RSM from above the inside rear
view mirror.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SIDE CURTAIN AIRBAG,
FRONT IMPACT SENSOR, SIDE IMPACT SENSOR,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
Fig. 15 Rain Sensor Module Remove/Install
1 - OVERHEAD CONSOLE
2 - REAR VIEW MIRROR CONNECTOR
3 - BRACKET
4 - REAR VIEW MIRROR BUTTON
5 - SPRING CLIP (2)
6 - RAIN SENSOR MODULE
7 - TRIM COVER
8 - WIRE HARNESS CONNECTOR
WJFRONT WIPERS/WASHERS 8R - 19
RAIN SENSOR MODULE (Continued)

²Continuous Rear Wipe Mode- The internal
circuitry and hardware of the right (wiper) multi-
function switch control sleeve provides one continu-
ous rear wipe switch position.
²Front Washer Mode- The internal circuitry
and hardware of the right (wiper) multi-function
switch control stalk provide front washer system
operation.
²Front Wipe-After-Wash Mode- The internal
circuitry and hardware of the right (wiper) multi-
function switch control stalk provide a wipe-after-
wash mode.
²Front Wiper Mist Mode- The internal cir-
cuitry and hardware of the right (wiper) multi-func-
tion switch control stalk provide a front wiper system
mist mode.
²Intermittent Front Wipe Mode- The internal
circuitry and hardware of the right (wiper) multi-
function switch control knob provide an intermittent
front wipe mode with five delay interval positions,
except on models equipped with the optional auto-
matic wiper system.
²Intermittent Rear Wipe Mode- The internal
circuitry and hardware of the right (wiper) multi-
function switch control ring provide one fixed inter-
val intermittent rear wipe mode switch position.
²Rear Washer Mode- The internal circuitry and
hardware of the right (wiper) multi-function switch
control stalk provide rear washer system operation.
OPERATION
The right (wiper) multi-function switch uses a com-
bination of resistor multiplexed and conventionally
switched outputs to control the many functions and
features it provides. The switch receives battery cur-
rent on a fused ignition switch output (run-acc) cir-
cuit from a fuse in the Junction Block (JB) whenever
the ignition switch is in the On or Accessory posi-
tions, and receives ground from the Body Control
Module (BCM) on a windshield wiper switch return
circuit. The right (wiper) multi-function switch may
be diagnosed using conventional diagnostic tools and
methods.
Following are descriptions of how the right (wiper)
multi-function switch control stalk operates to control
the functions and features it provides:
²Automatic Wipe Mode- On models equipped
with the optional automatic wiper system, the control
knob on the end of the right (wiper) multi-function
switch control stalk is rotated to one of five minor
intermediate detents to select the desired automatic
wipe sensitivity level. The control knob is rotated
rearward (counterclockwise) to reduce the sensitivity
(increase the interval between wipes), or forward
(clockwise) to increase the sensitivity (decrease the
interval between wipes). The right (wiper) multi-function switch provides a resistor multiplexed out-
put to the Body Control Module (BCM) on a
windshield wiper switch mux circuit. The BCM
responds by sending an electronic message to the
Rain Sensor Module (RSM) over the Programmable
Communications Interface (PCI) data bus indicating
the selected sensitivity level, and by operating the
front wiper system based upon electronic wipe com-
mands received from the RSM over the PCI data bus.
²Continuous Front Wipe Modes- The control
knob on the end of the right (wiper) multi-function
switch control stalk is rotated to an intermediate
detent that is one detent rearward (counterclockwise)
from the full forward (clockwise) detent to select the
low speed continuous front wiper mode, or to its full
forward (clockwise) detent to select the high speed
continuous front wiper mode. For the low speed
mode, the multi-function switch provides a resistor
multiplexed output to the Body Control Module
(BCM) on a windshield wiper switch mux circuit, and
the BCM responds by energizing the wiper on/off
relay in the Power Distribution Center (PDC) for the
front low speed continuous wipe mode. For the high
speed mode, the multi-function switch provides the
same resistor multiplexed output to the BCM on the
windshield wiper switch mux circuit as the low speed
mode, but also provides a ground output to the BCM
on a wiper high control circuit. The BCM responds to
these inputs by energizing the wiper on/off relay and
the wiper high/low relay in the PDC for the front
high speed continuous wipe mode.
²Continuous Rear Wipe Mode- The control
ring on the right (wiper) multi-function switch con-
trol stalk is rotated to the most forward (clockwise)
detent to select the continuous rear wiper mode. The
multi-function switch provides a battery current out-
put to the rear wiper motor on a rear wiper motor
control circuit to signal the rear wiper module to
operate the rear wiper motor in the continuous wipe
mode.
²Front Washer Mode- The control stalk of the
right (wiper) multi-function switch is pulled toward
the steering wheel to momentarily activate the front
washer pump/motor in the front washer mode. The
front washer pump will continue to operate in the
front washer mode until the control stalk is released.
The right (wiper) multi-function switch provides a
battery current output on a washer pump motor
switch output circuit to energize the front washer
pump in the front washer mode.
²Front Wiper Mist Mode- The control stalk of
the right (wiper) multi-function switch is pushed
towards the floor to momentarily activate the front
wiper motor in the mist mode. The front wiper motor
will continue to operate in the mist mode until the
control stalk is released. The right (wiper) multi-
WJFRONT WIPERS/WASHERS 8R - 21
RIGHT MULTI-FUNCTION SWITCH (Continued)

function switch provides a resistor multiplexed out-
put to the Body Control Module (BCM) on a
windshield wiper switch mux circuit, and the BCM
responds by energizing the wiper on/off relay in the
Power Distribution Center (PDC) to operate the front
wiper motor momentarily at low speed to provide the
front wiper mist mode.
²Intermittent Front Wipe Mode- On models
not equipped with the optional automatic wiper sys-
tem, the control knob on the end of the right (wiper)
multi-function switch control stalk is rotated to one
of five minor intermediate detents to select the
desired intermittent front wipe delay interval. The
control knob is rotated rearward (counterclockwise)
to increase the delay, or forward (clockwise) to
decrease the delay. The right (wiper) multi-function
switch provides a resistor multiplexed output to the
Body Control Module (BCM) on a windshield wiper
switch mux circuit. The BCM responds by monitoring
electronic vehicle speed messages received from the
Powertrain Control Module (PCM) over the Program-
mable Communications Interface (PCI) data bus,
then energizing the wiper on/off relay in the Power
Distribution Center (PDC) to operate the front wiper
motor at the proper delay intervals.
²Intermittent Rear Wipe Mode- The control
ring on the right (wiper) multi-function switch con-
trol stalk is rotated to the center detent to select the
intermittent rear wiper mode. The right (wiper)
multi-function switch provides a battery current out-
put to the rear wiper motor on a rear wiper motor
delay control circuit to signal the rear wiper module
to operate the rear wiper in the intermittent wipe
mode.
²Rear Washer Mode- The right (wiper) multi-
function switch control stalk is pushed forward
toward the instrument panel to a momentary posi-
tions to activate the rear washer pump/motor in the
rear washer mode. The rear washer pump will con-
tinue to operate in the rear washer mode until the
control stalk is released. The right (wiper) multi-
function switch provides battery current on a rear
washer pump motor control circuit to energize the
rear washer pump in the rear washer mode.DIAGNOSIS AND TESTING - RIGHT MULTI-
FUNCTION SWITCH
Be certain to perform the diagnosis for the front
wiper system, front washer system, rear wiper sys-
tem, and/or rear washer system before testing the
right multi-function switch. (Refer to 8 - ELECTRI-
CAL/FRONT WIPERS/WASHERS - DIAGNOSIS
AND TESTING) or (Refer to 8 - ELECTRICAL/REAR
WIPERS/WASHERS - DIAGNOSIS AND TESTING).
Refer to the appropriate wiring information. The wir-
ing 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 connectors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE PASSIVE RESTRAINT SYS-
TEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG. SIDE CURTAIN AIRBAG,
FRONT IMPACT SENSOR, SIDE IMPACT SENSOR,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE PASSIVE RESTRAINT
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the right multi-function switch from
the steering column and disconnect the instrument
panel wire harness connector for the switch from the
switch connector receptacle.
(3) Using an ohmmeter, check the right multi-func-
tion switch continuity and resistances at the switch
terminals as shown in the Right Multi-Function
Switch test chart (Fig. 17).
8R - 22 FRONT WIPERS/WASHERSWJ
RIGHT MULTI-FUNCTION SWITCH (Continued)

switch mounting housing. Tighten the screws to 2.5
N´m (22 in. lbs.).
(3) Reconnect the instrument panel wire harness
connector for the right multi-function switch to the
switch connector receptacle.
(4) Position the lower tilting steering column
shroud to the underside of the steering column (Fig.
18).
(5) Install and tighten the screw that secures the
lower tilting steering column shroud to the multi-
function switch mounting housing. Tighten the screw
to 1.9 N´m (17 in. lbs.).
(6) Position the upper tilting column shroud over
the steering column with the hazard warning switch
button inserted through the hole in the upper surface
of the shroud. Align the upper tilting steering column
shroud to the lower shroud and snap the two shroud
halves together.
(7) Reconnect the battery negative cable.
WASHER FLUID LEVEL
SWITCH
DESCRIPTION
The washer fluid level switch is a single pole, sin-
gle throw reed-type switch mounted near the front of
the washer reservoir, forward of the two washer
pump/motors (Fig. 20). Only the molded plastic
switch mounting flange and connector receptacle are
visible when the switch is installed in the reservoir.A short nipple formation extends from the inner sur-
face of the switch mounting flange, and a barb on the
nipple near the switch mounting flange is press-fit
into a rubber grommet seal installed in the mounting
hole of the reservoir. A small plastic float pivots on
the end of a bracket that extends from the switch
nipple formation. Within the float is a small magnet,
which actuates the reed switch. The washer fluid
level switch cannot be adjusted or repaired. If faulty
or damaged, the switch must be replaced.
OPERATION
The washer fluid level switch uses a pivoting,
oblong float to monitor the level of the washer fluid
in the washer reservoir. The float contains a small
magnet. When the float pivots, the changing proxim-
ity of its magnetic field will cause the contacts of the
small, stationary reed switch to open or close. When
the fluid level in the washer reservoir is at or above
the float level, the float moves to a vertical position
and the switch contacts open. When the fluid level in
the washer reservoir falls below the pivoting float,
the float moves to a horizontal position and the
switch contacts close. The switch is connected to the
vehicle electrical system through a dedicated take
out and connector of the left headlamp and dash wire
harness. The switch receives a five volt reference sig-
nal from the Body Control Module (BCM) through
the washer fluid switch output circuit. The switch is
grounded at all times through another take out of
the left headlamp and dash wire harness with a sin-
gle eyelet terminal connector that is secured under a
ground screw near the top of the left front fender
inner shield in the engine compartment.
When the switch closes, the BCM senses the volt-
age change on the circuit. The BCM is programmed
to send low washer fluid messages to the Electronic
Vehicle Information Center (EVIC) over the Program-
mable Communications Interface (PCI) data bus. The
EVIC is programmed to respond to this message by
displaying the Washer Fluid Low warning and send-
ing a chime request message back to the BCM over
the PCI data bus. Then the BCM generates an audi-
ble chime tone warning. A resistor within the washer
fluid level switch allows the BCM to monitor and
diagnose this circuit. The BCM will store a Diagnos-
tic Trouble Code (DTC) for any fault that it detects.
For retrieval of this fault information and further
diagnosis of the washer fluid level switch, the BCM,
the EVIC, the PCI data bus, the BCM message out-
puts to the EVIC that control the Low Washer Fluid
indicator, or the EVIC message outputs to the BCM
that control chime service, a DRBIIItscan tool and
the appropriate diagnostic information are required.
Fig. 20 Washer Fluid Level Switch (Viewed from
Bottom of Reservoir)
1 - REAR WASHER PUMP/MOTOR
2 - FRONT WASHER PUMP/MOTOR
3 - WASHER FLUID LEVEL SWITCH
WJFRONT WIPERS/WASHERS 8R - 25
RIGHT MULTI-FUNCTION SWITCH (Continued)

REAR WIPERS/WASHERS
TABLE OF CONTENTS
page page
REAR WIPERS/WASHERS
DESCRIPTION.........................33
OPERATION...........................34
DIAGNOSIS AND TESTING - REAR WIPER &
WASHER SYSTEM....................35
CLEANING - REAR WIPER & WASHER
SYSTEM............................37
INSPECTION - REAR WIPER & WASHER
SYSTEM............................37
REAR WASHER HOSES/TUBES
DESCRIPTION.........................38
OPERATION...........................39
REAR WASHER NOZZLE
DESCRIPTION.........................39
OPERATION...........................39
REMOVAL.............................39
INSTALLATION.........................40
REAR WASHER PUMP/MOTOR
DESCRIPTION.........................40
OPERATION...........................40REMOVAL.............................41
INSTALLATION.........................41
REAR WIPER ARM
DESCRIPTION.........................41
OPERATION...........................42
REMOVAL.............................42
INSTALLATION.........................42
REAR WIPER BLADE
DESCRIPTION.........................43
OPERATION...........................43
REMOVAL.............................44
INSTALLATION.........................44
REAR WIPER MODULE
DESCRIPTION.........................44
OPERATION...........................45
REMOVAL.............................45
INSTALLATION.........................45
WIPER ARM PARK RAMP
REMOVAL.............................46
INSTALLATION.........................46
REAR WIPERS/WASHERS
DESCRIPTION
An electrically operated fixed interval intermittent
rear wiper and washer system is standard factory-in-
stalled equipment on this model. The rear wiper and
washer system includes the following major compo-
nents, which are described in further detail else-
where in this service information:
²Rear Washer Nozzle- The rear washer nozzle
is secured by a snap fit onto the top of the liftgate
outer panel above the liftgate glass. The rear washer
nozzle includes an integral check valve. The rear
washer system plumbing is concealed within and
routed through the interior of the vehicle.
²Rear Washer Pump/Motor- The rear washer
pump/motor unit is located in a dedicated hole on the
lower outboard side of the washer reservoir, ahead of
the left front wheel housing. The rear washer pump
mounting hole is located higher on the reservoir than
the front washer pump mounting hole.
²Rear Wiper Arm- The single rear wiper arm is
secured by a nut directly to the rear wiper module
output shaft, which extends through the liftgate
outer panel near the base of the liftgate glass.²Rear Wiper Arm Park Ramp- The molded
rubber rear wiper arm park ramp is secured with a
screw to the liftgate outer panel, just below the right
side of the liftgate glass. When the rear wiper system
is not in operation, the rear wiper arm is parked on
this ramp so that it will not interfere with or be
damaged by liftgate flip-up glass operation.
²Rear Wiper Blade- The single rear wiper
blade is secured to the rear wiper arm, and is moved
off of the liftgate glass when the rear wiper system is
not in operation.
²Rear Wiper Module- The rear wiper module
output shaft is the only visible component of the rear
wiper module. The remainder of the module is con-
cealed within the liftgate beneath the liftgate glass
opening. The rear wiper module includes the module
bracket, the rear wiper motor, and the rear wiper
module electronic control circuitry.
²Right Multi-Function Switch- The right
(wiper) multi-function switch is secured to the right
side of the multi-function switch mounting housing
near the top of the steering column. Only the control
stalk for the right multi-function switch is visible,
the remainder of the switch is concealed beneath the
steering column shrouds. The right multi-function
switch contains all of the switches and control cir-
cuitry for both the front and rear wiper and washer
systems.
WJREAR WIPERS/WASHERS 8R - 33

²Washer Reservoir- The rear washer system
shares a single reservoir with the front washer sys-
tem, but has its own dedicated washer pump/motor
and plumbing. The washer reservoir is concealed
between the left inner fender shield and the left
outer fender panel, behind the inner fender liner and
ahead of the left front wheel. The washer reservoir
filler neck is the only visible portion of the reservoir,
and it is accessed from the left front corner of the
engine compartment.
Features of the rear wiper and washer system
include the following:
²Continuous Wipe Mode- When the right
multi-function switch control sleeve is moved to the
On position, the rear wiper will be operated at a
fixed speed, continual wipe cycle until the switch
sleeve is moved to the Delay or Off positions, until
the ignition switch is turned to the Off position, or
until the liftgate flip-up glass is ajar.
²Intermittent Wipe Mode- When the right
multi-function switch control sleeve is moved to the
Delay position, the rear wiper will be operated in a
fixed interval, intermittent wipe cycle until the
switch sleeve is moved to the On or Off positions,
until the ignition switch is turned to the Off position,
until the liftgate flip-up glass is ajar, or until the
right multi-function switch control stalk is pushed
forward to activate the rear washer system. The
intermittent wipe mode delay time has a fixed delay
interval of about five to eight seconds between
sweeps.
²Washer Mode- When the right multi-function
switch control stalk is pushed forward to activate the
rear washer system, washer fluid will be dispensed
from the washer reservoir onto the liftgate glass
through the rear washer nozzle and the rear wiper
will operate in a fixed cycle (not intermittent) for as
long as the rear washer pump/motor unit remains
energized. When the control stalk is released from
the momentary Wash position, the wipe-after-wash
feature will continue to operate the rear wiper at a
fixed cycle for about three additional wiper sweeps
before returning to the previously selected mode.
Hard wired circuitry connects the rear wiper and
washer system components to the electrical system of
the vehicle. These hard wired circuits are integral to
several 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 rear wiper and
washer system components through the use of a com-
bination of soldered splices, splice block connectors,
and many different types of wire harness terminal
connectors and insulators. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repairprocedures, further details on wire harness routing
and retention, as well as pin-out and location views
for the various wire harness connectors, splices and
grounds.
OPERATION
The rear wiper and washer system is intended to
provide the vehicle operator with a convenient, safe,
and reliable means of maintaining visibility through
the liftgate glass. The various components of this sys-
tem are designed to convert electrical energy pro-
duced by the vehicle electrical system into the
mechanical action of the wiper blade to wipe the out-
side surface of the glass, as well as into the hydraulic
action of the washer system to apply washer fluid
stored in an on-board reservoir to the area of the
glass to be wiped. When combined, these components
provide the means to effectively maintain clear visi-
bility for the vehicle operator by removing excess
accumulations of rain, snow, bugs, mud, or other
minor debris from the outside liftgate glass surface
that might be encountered while driving the vehicle
under numerous types of inclement operating condi-
tions. The vehicle operator initiates all rear wiper
and washer system functions with the right multi-
function switch located on the right side of the steer-
ing column, just below the steering wheel. Moving
the switch control sleeve to a detent position selects
the rear wiper system operating mode. Moving the
switch control stalk forward to a momentary position
activates the rear washer pump/motor, which dis-
penses washer fluid onto the liftgate glass through
the rear washer nozzle and operates the rear wiper
system in the fixed cycle mode for as long as the
washer switch is closed plus about three wiper
sweeps.
When the ignition switch is in the Accessory or On
positions, battery current from a fuse in the Junction
Block (JB) is provided to the right multi-function
switch through a fused ignition switch output (run-
acc) circuit. A separate fuse in the JB provides bat-
tery current to the electronic control circuitry of the
rear wiper module through a fused B(+) circuit.
When the right multi-function switch control sleeve
On position is selected, the On position circuitry
within the switch directs a battery current rear
wiper motor control signal input to the rear wiper
module electronic circuitry, which causes the rear
wiper motor to run at a fixed continuous wipe cycle.
When the right multi-function switch control sleeve
Delay position is selected, the Delay position cir-
cuitry within the switch directs a battery current
rear washer switch output signal input to the rear
wiper module electronic circuitry, which causes the
rear wiper motor to run at a fixed intermittent wipe
cycle. When the right multi-function switch control
8R - 34 REAR WIPERS/WASHERSWJ
REAR WIPERS/WASHERS (Continued)

stalk is moved to the rear Wash position, the Wash
position circuitry within the switch directs battery
current to the rear washer pump/motor unit, and to
both the rear wiper motor control and rear washer
switch output signal inputs of the rear wiper module
electronic circuitry, which causes the wiper motor to
run at a fixed cycle for as long as the Wash mode is
selected plus about three additional fixed wipe cycles.
The rear wiper module electronic circuitry controls
the switching of battery current to the rear wiper
motor brush, which controls wiper motor operation.
The intermittent wipe and wipe-after-wash features
of the rear wiper and washer system are both pro-
vided by the rear wiper module electronic circuitry.
The rear wiper module electronic circuitry also mon-
itors the liftgate flip-up glass ajar switch and will
park the rear wiper blade off of the glass any time it
senses that the liftgate flip-up glass is ajar, the igni-
tion switch is turned to the Off position, or the right
multi-function switch control sleeve is moved to the
Off position. This feature ensures that the rear wiper
blade will not interfere with or be damaged by the
operation of the liftgate flip-up glass. However, if the
ignition switch is turned to the Off position or the
liftgate flip-up glass is opened while the rear wiper is
operating, the right multi-function switch control
sleeve must be cycled to the Off position and back to
the On or Delay position after the ignition switch is
turned back On or the liftgate flip-up glass is closed
before the rear wiper will operate again.
Refer to the owner's manual in the vehicle glove
box for more information on the features and opera-
tion of the rear wiper and washer system.
DIAGNOSIS AND TESTING - REAR WIPER &
WASHER SYSTEM
WIPER SYSTEM
The diagnosis found here addresses an electrically
inoperative rear wiper system. If the rear wiper
motor operates, but the wiper does not move on the
liftgate glass, replace the faulty rear wiper module. If
the wiper operates, but chatters, lifts, or does not
clear the glass, clean and inspect the wiper system
components as required. (Refer to 8 - ELECTRICAL/
REAR WIPERS/WASHERS - INSPECTION) and
(Refer to 8 - ELECTRICAL/REAR WIPERS/WASH-
ERS - CLEANING). Refer to the appropriate wiring
information. The wiring information includes wiring
diagrams, proper wire and connector repair proce-
dures, details of wire harness routing and retention,
connector pin-out information and location views for
the various wire harness connectors, splices and
grounds.WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Check that the interior lighting switch on the
control stalk of the left multi-function switch is not
in the dome lamp disable position. With all four
doors and the liftgate closed, open the liftgate flip-up
glass. The interior lamps should light. If not, depress
the cargo lamp lens to actuate the cargo lamp defeat
switch and the interior lamps should light. Close all
four doors, the liftgate and the liftgate flip-up glass.
Note whether the interior lamps remain lighted.
They should turn off after about thirty seconds. If
OK, go to Step 2. If not OK, go to Step 9.
(2) Check the fused B(+) fuse (Fuse8-15ampere)
in the Junction Block (JB). If OK, go to Step 3. If not
OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(3) Check for battery voltage at the fused B(+) fuse
(Fuse8-15ampere) in the JB. If OK, go to Step 4. If
not OK, repair the open fused B(+) circuit between
the JB and the Power Distribution Center (PDC) as
required.
(4) Check the fused ignition switch output (run-
acc) fuse (Fuse 29 - 10 ampere) in the JB. If OK, go
to Step 5. If not OK, repair the shorted circuit or
component as required and replace the faulty fuse.
(5) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-acc) fuse (Fuse 29 - 10 ampere) in the
JB. If OK, turn the ignition switch to the Off position
and go to Step 6. If not OK, repair the open fused
ignition switch output (run-acc) circuit between the
JB and the ignition switch as required.
(6) Disconnect and isolate the battery negative
cable. Disconnect the instrument panel wire harness
connector for the right multi-function switch from the
switch connector receptacle. Reconnect the battery
negative cable. Turn the ignition switch to the On
position. Check for battery voltage at the fused igni-
tion switch output (run-acc) circuit cavity of the
instrument panel wire harness connector for the
right multi-function switch. If OK, go to Step 7. If
not OK, repair the open fused ignition switch output
WJREAR WIPERS/WASHERS 8R - 35
REAR WIPERS/WASHERS (Continued)

motor that is secured with screws to the wiper motor
and to the liftgate inner panel.
²Electronic Controls- The rear wiper module
electronic controls include the rear wiper system
electronic logic and rear wiper motor electronic con-
trols. The electronic controls for the motor include an
electronic speed control that speeds the wiper blade
near the center of the glass, but slows the wiper
blade during directional reversals at each end of the
wipe pattern and during wiper blade off-the-glass
parking for quieter operation.
²Motor- The permanent magnet rear wiper
motor is secured with screws to the rear wiper mod-
ule bracket. The wiper motor includes an integral
transmission, and the motor output shaft.
The rear wiper module cannot be adjusted or
repaired. If any component of the module is faulty or
damaged, the entire rear wiper module unit must be
replaced. The motor output shaft gasket, bezel, nut,
and nut cover are available for service replacement.
OPERATION
The rear wiper module receives non-switched bat-
tery current through a fuse in the Junction Block
(JB) and is grounded at all times. The rear wiper
module operation is controlled by the vehicle operator
through battery current signal inputs received by the
rear wiper module electronic controls from the right
multi-function switch on the steering column. The
module also receives an external control input from
the liftgate flip-up glass ajar switch circuit. The rear
wiper module electronic control logic uses these
inputs, its internal inputs, and its programming to
provide continuous wipe, delay wipe, wipe-after-wash
and off-the-glass wiper blade parking. The wiper
blade cycling is controlled by the rear wiper module
electronic controls, which control current flow to the
wiper motor brushes. The wiper motor transmission
converts the rotary output of the wiper motor to the
back and forth wiping motion of the rear wiper arm
and blade on the liftgate glass.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the rear wiper arm from the rear
wiper motor output shaft. (Refer to 8 - ELECTRI-
CAL/REAR WIPERS/WASHERS/REAR WIPER ARM
- REMOVAL).
(3) Use a door trim panel removal tool to gently
pry at the base of the nut cover where it meets the
wiper motor output shaft bezel and gasket on the
outer liftgate panel until it unsnaps from the bezel
(Fig. 13). Be certain to use proper caution to protect
the outer liftgate panel and its paint finish from
damage during this procedure.(4) Remove the nut that secures the rear wiper
motor output shaft to the outer liftgate panel.
(5) Remove the bezel and gasket from the rear
wiper motor output shaft.
(6) Remove the trim panel from the inside of the
liftgate. (Refer to 23 - BODY/DECKLID/HATCH/
LIFTGATE/TAILGATE/TRIM PANEL - REMOVAL).
(7) Disconnect the liftgate wire harness connector
for the rear wiper module from the module connector
receptacle (Fig. 14).
(8) Loosen the two nuts that secure the rear wiper
module mounting bracket to the liftgate inner panel.
(9) Slide the rear wiper module and mounting
bracket forward far enough to disengage the mount-
ing nuts from the keyed holes in the liftgate inner
panel.
(10) Remove the rear wiper module and mounting
bracket from the liftgate as a unit.
INSTALLATION
(1) Position the rear wiper module and bracket to
the liftgate as a unit (Fig. 14).
(2) Insert the rear wiper motor output shaft
through the hole in the liftgate outer panel and
engage the mounting nuts in the keyed holes in the
liftgate inner panel.
(3) From the outside of the liftgate, center the rear
wiper motor output shaft in the liftgate outer panel
mounting hole and install the gasket and bezel over
the centered shaft (Fig. 13).
Fig. 13 Rear Wiper Motor Output Shaft Remove/
Install
1 - NUT
2 - NUT COVER
3 - BEZEL AND GASKET
4 - LIFTGATE OUTER PANEL
5 - REAR WIPER MOTOR OUTPUT SHAFT
WJREAR WIPERS/WASHERS 8R - 45
REAR WIPER MODULE (Continued)