2002 JEEP GRAND CHEROKEE Tire

(1) The rear wiper arm must be indexed to the
motor output shaft with the rear wiper motor in the
park position to be properly installed. Place the
wiper arm onto the liftgate with the wiper arm sup-
port positioned on the park ramp and the pivot hole
on the end of the arm positioned over the rear wiper
motor output shaft.
(2) Position the ridge of the wiper arm support on
the liftgate park ramp in the Installation Position
(Fig. 10).
(3) With the wiper arm in the Installation Posi-
tion, push the pivot hole on the end of the wiper arm
down over the rear wiper motor output shaft.
(4) Install and tighten the nut that secures the
rear wiper arm to the rear wiper motor output shaft.
Tighten the nut to 18 N´m (160 in. lbs.).
(5) Close the rear wiper arm pivot cover.(6) Lift the rear wiper arm support away from the
park ramp, then place the wiper arm support in the
park ramp in the Park Position (Fig. 10).
REAR WIPER BLADE
DESCRIPTION
The rear wiper blade is secured by an integral
latching pivot block to the hook formation on the tip
of the rear wiper arm, and rests off the glass near
the base of the liftgate glass opening when the wiper
is not in operation. The wiper blade consists of the
following components:
²Superstructure- The superstructure includes
a stamped steel bridge and plastic links with claw
formations that grip the wiper blade element. Also
included in this unit is the latching, molded plastic
pivot block that secures the superstructure to the
wiper arm. All of the metal components of the wiper
blade have a satin black finish applied.
²Element- The wiper element or squeegee is the
resilient rubber member of the wiper blade that con-
tacts the glass.
²Flexor- The flexor is a rigid metal component
running along the length of each side of the wiper
element where it is gripped by the claws of the
superstructure.
All Grand Cherokee models have a single 31.00
centimeter (12.20 inch) rear wiper blade with a non-
replaceable rubber element (squeegee). The wiper
blade cannot be adjusted or repaired. If faulty, worn,
or damaged the entire wiper blade unit must be
replaced.
OPERATION
The wiper blade is moved back and forth across the
glass by the wiper arm when the wiper system is in
operation. The wiper blade superstructure is the flex-
ible frame that grips the wiper blade element and
evenly distributes the force of the spring-loaded
wiper arm along the length of the element. The com-
bination of the wiper arm force and the flexibility of
the superstructure makes the element conform to
and maintain proper contact with the glass, even as
the blade is moved over the varied curvature found
across the glass surface. The wiper element flexor
provides the claws of the blade superstructure with a
rigid, yet flexible component on the element which
can be gripped. The rubber element is designed to be
stiff enough to maintain an even cleaning edge as it
is drawn across the glass, but resilient enough to
conform to the glass surface and flip from one clean-
ing edge to the other each time the wiper blade
changes directions.
Fig. 10 Rear Wiper Arm Installation
1 - LIFTGATE
2 - PARK RAMP
3 - REAR WIPER ARM
4 - INSTALLATION POSITION
5 - REAR WIPER ARM AND BLADE
6 - PARK POSITION
7 - PARK RAMP
8 - LIFTGATE
WJREAR WIPERS/WASHERS 8R - 43
REAR WIPER ARM (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)

DESCRIPTION - CIRCUIT FUNCTIONS
All circuits in the diagrams use an alpha/numeric
code to identify the wire and it's function. To identify
which circuit code applies to a system, refer to the
Circuit Identification Code Chart. This chart shows
the main circuits only and does not show the second-
ary codes that may apply to some models.
CIRCUIT IDENTIFICATION CODE CHART
CIRCUIT FUNCTION
A BATTERY FEED
B BRAKE CONTROLS
C CLIMATE CONTROLS
D DIAGNOSTIC CIRCUITS
E DIMMING ILLUMINATION
CIRCUITS
F FUSED CIRCUITS
G MONITORING CIRCUITS
(GAUGES)
H OPEN
I NOT USED
J OPEN
K POWERTRAIN CONTROL
MODULE
L EXTERIOR LIGHTING
M INTERIOR LIGHTING
N NOT USED
O NOT USED
P POWER OPTION (BATTERY
FEED)
Q POWER OPTIONS (IGNITION
FEED)
R PASSIVE RESTRAINT
S SUSPENSION/STEERING
T TRANSMISSION/TRANSAXLE/
TRANSFER CASE
U OPEN
V SPEED CONTROL, WIPER/
WASHER
W OPEN
X AUDIO SYSTEMS
Y OPEN
Z GROUNDS
DESCRIPTION - SECTION IDENTIFICATION AND
INFORMATION
The wiring diagrams are grouped into individual
sections. If a component is most likely found in a par-
ticular group, it will be shown complete (all wires,
connectors, and pins) within that group. For exam-
ple, the Auto Shutdown Relay is most likely to be
found in Group 30, so it is shown there complete. It
can, however, be shown partially in another group if
it contains some associated wiring.
Splice diagrams in Section 8W-70 show the entire
splice and provide references to other sections the
splices serves. Section 8W-70 only contains splice dia-
grams that are not shown in their entirety some-
where else in the wiring diagrams.
Section 8W-80 shows each connector and the cir-
cuits involved with that connector. The connectors
are identified using the name/number on the dia-
gram pages.
WIRING SECTION CHART
GROUP TOPIC
8W-01 thru
8W-09General information and Diagram
Overview
8W-10 thru
8W-19Main Sources of Power and
Vehicle Grounding
8W-20 thru
8W-29Starting and Charging
8W-30 thru
8W-39Powertrain/Drivetrain Systems
8W-40 thru
8W-49Body Electrical items and A/C
8W-50 thru
8W-59Exterior Lighting, Wipers and
Trailer Tow
8W-60 thru
8W-69Power Accessories
8W-70 Splice Information
8W-80 Connector Pin Outs
8W-91 Connector, Ground and Splice
Locations
8W - 01 - 6 8W-01 WIRING DIAGRAM INFORMATIONWJ
WIRING DIAGRAM INFORMATION (Continued)

WIRE
STANDARD PROCEDURE - WIRE SPLICING
When splicing a wire, it is important that the cor-
rect gage be used as shown in the wiring diagrams.
(1) Remove one-half (1/2) inch of insulation from
each wire that needs to be spliced.
(2) Place a piece of adhesive lined heat shrink tub-
ing on one side of the wire. Make sure the tubing will
be long enough to cover and seal the entire repair
area.
(3) Place the strands of wire overlapping each
other inside of the splice clip (Fig. 14).
(4) Using crimping tool, Mopar p/n 05019912AA,
crimp the splice clip and wires together (Fig. 15).(5) Solder the connection together using rosin core
type solder only (Fig. 16).
CAUTION: DO NOT USE ACID CORE SOLDER.
(6) Center the heat shrink tubing over the joint
and heat using a heat gun. Heat the joint until the
tubing is tightly sealed and sealant comes out of both
ends of the tubing (Fig. 17).
Fig. 14 SPLICE BAND
1 - SPLICE BAND
Fig. 15 CRIMPING TOOL
1 - CRIMPING TOOL
Fig. 16 SOLDER SPLICE
1 - SOLDER
2 - SPLICE BAND
3 - SOLDERING IRON
Fig. 17 HEAT SHRINK TUBE
1 - SEALANT
2 - HEAT SHRINK TUBE
WJ8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 15

JUNCTION BLOCK
DESCRIPTION
An electrical Junction Block (JB) is concealed
beneath the driver side of the instrument panel in
the passenger compartment of the vehicle (Fig. 3).
The JB combines the functions previously provided
by a separate fuseblock module and relay center. The
JB serves to simplify and centralize numerous elec-
trical components, as well as to distribute electrical
current to many of the accessory systems in the vehi-
cle. It also eliminates the need for numerous splice
connections. The JB houses up to thirty-three blade-
type mini fuses, up to two blade-type automatic
resetting circuit breakers, the electronic combination
flasher, the Daytime Running Lamp (DRL) module
(Canada only) and up to twelve International Stan-
dards Organization (ISO) relays (three standard-type
and nine micro-type). The JB also incorporates an
integral connector and mounting for the Body Con-
trol Module (BCM). The BCM is secured with four
screws directly to the dash panel side of the JB.
Refer toBody Control Modulein Electronic Con-
trol Modules for additional information covering the
BCM.
The molded plastic JB housing has integral mounts
that are secured with two screws and two snap
retainers to the instrument panel steering column
support bracket behind the instrument panel steer-ing column opening cover. The JB is concealed above
the molded plastic instrument panel fuse cover. Inte-
gral latches molded into the fuse cover secure it the
JB, the BCM and the 16-way data link connector tab
of the instrument panel steering column support
bracket. The fuse cover can be pulled downward to
disengage the latches and provide service access to
all of the fuses, relays and wire harness connectors of
the JB. The fuse cover has a fuse puller and spare
fuses secured to its upper surface. Refer toInstru-
ment Panel Fuse Coverin Body for additional ser-
vice information.
The JB unit cannot be repaired and is only ser-
viced as an assembly. If any internal circuit or the JB
housing is faulty or damaged, the entire JB unit
must be replaced. The BCM is available for separate
service replacement.
OPERATION
All of the circuits entering and leaving the Junc-
tion Block (JB) do so through up to five wire harness
connectors, which are connected to the JB through
integral connector receptacles molded into the JB
housing. Internal connection of all of the JB circuits
is accomplished by a printed circuit board. There are
also two separate wire harness connections to con-
nector receptacles that are integral to the BCM.
Refer toJunction Blockin Wiring Diagrams for
additional information and the location of complete
JB circuit diagrams.
REMOVAL
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE AIRBAG SYSTEM CAPACITOR TO DISCHARGE
BEFORE PERFORMING FURTHER DIAGNOSIS OR
SERVICE. THIS IS THE ONLY SURE WAY TO DIS-
ABLE THE AIRBAG SYSTEM. FAILURE TO TAKE
THE PROPER PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSI-
BLE PERSONAL INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the fuse cover from the bottom of the
Junction Block (JB).
(3) Remove the steering column opening cover
from the instrument panel. Refer toSteering Col-
umn Opening Coverin Body for the location of
steering column opening cover removal procedures.
Fig. 3 Junction Block Location
1 - REAR LATCHES
2 - JUNCTION BLOCK AND BODY CONTROL MODULE UNIT
3 - INSTRUMENT PANEL FUSE COVER
4 - SIDE LATCH
5 - FRONT LATCHES
WJ8W-97 POWER DISTRIBUTION 8W - 97 - 5

are only serviced as a unit with the right headlamp
and dash wire harness. If the PDC main housing
unit, fuse wedges or the bus bars are faulty or dam-
aged, the right headlamp and dash wire harness unit
must be replaced.
OPERATION
All of the current from the battery and the generator
output enters the PDC through two cables and a single
two-holed eyelet that is secured with nuts to the two
PDC B(+) terminal studs just inside the front end of the
PDC housing. The PDC cover is unlatched and opened
to access the battery and generator output connection
B(+) terminal studs, the fuses or the relays. Internal
connection of all of the PDC circuits is accomplished by
an intricate combination of hard wiring and bus bars.
Refer toPower Distribution
in Wiring Diagrams for
the location of complete PDC circuit diagrams.
REMOVAL
The Power Distribution Center (PDC) main housing
unit, the PDC fuse wedges and the PDC bus bars can-
not be repaired and are only serviced as a unit with the
right headlamp and dash wire harness. If the PDC
main housing unit, the fuse wedges or the bus bars are
faulty or damaged, the entire PDC and right headlamp
and dash wire harness unit must be replaced.
(1)Disconnect and isolate the battery negative cable.
(2) Disconnect each of the right headlamp and
dash wire harness connectors. Refer toConnector
Locationsin Wiring Diagrams for the location of
more information on the right headlamp and dash
wire harness connector locations.
(3) Remove all of the fasteners that secure each of
the right headlamp and dash wire harness ground
eyelets to the vehicle body and chassis components.
Refer toConnector Locationsin Wiring Diagrams
for the location of more information on the ground
eyelet locations.
(4) Disengage each of the retainers that secure the
right headlamp and dash wire harness to the vehicle
body and chassis components. Refer toConnector
Locationsin Wiring Diagrams for the location of
more information on the right headlamp and dash
wire harness retainer locations.
(5) Unlatch and open the PDC cover.
(6) Remove the two nuts that secure the two-holed
eyelet of the battery wire harness PDC take outs to
the PDC B(+) terminal studs (Fig. 8).
(7) Remove the battery wire harness PDC take out
eyelet from the B(+) terminal studs.
(8) Disengage the latches on the PDC housing
mounts from the tabs on the PDC mounting stan-
chions of the battery support, and pull the PDC
housing upward to disengage the mounts from the
stanchions (Fig. 9).
Fig. 8 Power Distribution Center Connections
1 - PDC COVER
2 - NUT (2)
3 - EYELET
4 - B(+) TERMINAL STUDS
Fig. 9 Power Distribution Center Remove/Install
1 - POWER DISTRIBUTION CENTER
2 - MOUNTS
3 - STANCHIONS (3)
4 - BATTERY SUPPORT
8W - 97 - 8 8W-97 POWER DISTRIBUTIONWJ
POWER DISTRIBUTION CENTER (Continued)

PDC LOWER COVER INSTALLATION
(1) Align the PDC housing lower cover on the bot-
tom of the PDC.
(2) Evenly press the lower cover into place until
latches are fully engaged.
(3) Where the right headlamp and dash harness
enters the PDC, tape the harness securely to the
trough formation on the PDC lower cover.
(4) Install the PDC in its mounting location on the
battery support.
(5) Install the battery wire harness over the two
PDC B+ terminal studs. Torque the nuts to 11.3 N´m
(100 in. lbs.).
(6) Install the battery. Refer to Battery System for
the procedure.
(7) Install the PDC cover.
INSTALLATION
The Power Distribution Center (PDC) main hous-
ing unit, the PDC fuse wedges and the PDC bus bars
cannot be repaired and are only serviced as a unit
with the right headlamp and dash wire harness. If
the PDC main housing unit, the fuse wedges or the
bus bars are faulty or damaged, the entire PDC and
right headlamp and dash wire harness unit must be
replaced.
(1) Position the PDC and the right headlamp and
dash wire harness unit in the engine compartment.
(2) Engage the PDC housing mounts with the
stanchions of the battery support and push the unit
downward until the mount latches fully engage the
mounting tabs on the stanchions.
(3) Install the two-holed eyelet of the battery wire
harness PDC take outs onto the two PDC B(+) termi-
nal studs.
(4) Install and tighten the nuts that secure the
eyelet of the battery wire harness PDC take outs to
the B(+) terminal studs. Tighten the nuts to 11.3
N´m (100 in. lbs.).
(5) Engage each of the retainers that secure the
right headlamp and dash wire harness to the vehicle
body and chassis components. Refer toConnector
Locationsin Wiring Diagrams for the location of
more information on the right headlamp and dash
wire harness retainer locations.
(6) Install all of the fasteners that secure each of
the right headlamp and dash wire harness ground
eyelets to the vehicle body and chassis components.
Refer toConnector Locationsin Wiring Diagrams
for the location of more information on the ground
eyelet locations.
(7) Reconnect each of the right headlamp and dash
wire harness connectors. Refer toConnector Loca-
tionsin Wiring Diagrams for the location of more
information on the right headlamp and dash wire
harness connector locations. For connectors securedwith screws, tighten the screws to 4.3 N´m (38 in.
lbs.).
(8) Reconnect the battery negative cable.
POWER OUTLET
DESCRIPTION - FRONT POWER OUTLET
An accessory power outlet is standard equipment
on this model. The power outlet is installed in the
instrument panel center lower bezel, which is located
near the bottom of the instrument panel center stack
area, below the heater and air conditioner controls.
The power outlet base is secured by a snap fit within
the center lower bezel. A hinged door with an over-
center spring flips closed to conceal and protect the
power outlet base when the power outlet is not being
used, and flips open below the center lower bezel
while the power outlet is in use.
The power outlet receptacle unit and the power
outlet door are each available for service replace-
ment.
OPERATION - FRONT POWER OUTLET
The power outlet base or receptacle shell is con-
nected to ground, and an insulated contact in the
bottom of the shell is connected to battery current.
The power outlet receives battery voltage from a fuse
in the junction block at all times.
While the power outlet is very similar to a cigar
lighter base unit, it does not include the two small
spring-clip retainers inside the bottom of the recepta-
cle shell that are used to secure the cigar lighter
heating element to the insulated contact.
DIAGNOSIS AND TESTING - POWER OUTLET
For complete circuit diagrams, refer toHorn/Ci-
gar Lighter/Power Outletin Wiring Diagrams.
WARNING: REFER TO RESTRAINTS BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Check the fused B(+) fuse in the junction block.
If OK, go to Step 2. If not OK, repair the shorted cir-
cuit or component as required and replace the faulty
fuse.
(2) Check for battery voltage at the fused B(+) fuse
in the junction block. If OK, go to Step 3. If not OK,
repair the open fused B(+) circuit to the Power Dis-
tribution Center (PDC) fuse as required.
(3) Open the power outlet door. Check for continu-
ity between the inside circumference of the power
8W - 97 - 12 8W-97 POWER DISTRIBUTIONWJ
POWER DISTRIBUTION CENTER (Continued)

BEARING-TO-JOURNAL CLEARANCE
(1) Wipe the oil from the connecting rod journal.
(2) Use short rubber hose sections over rod bolts
during installation.
(3) Lubricate the upper bearing insert and install
in connecting rod.
(4) Use piston ring compressor to install the rod
and piston assemblies. The oil squirt holes in the
rods must face the camshaft. The arrow on the piston
crown should point to the front of the engine (Fig.
38). Verify that the oil squirt holes in the rods face
the camshaft and that the arrows on the pistons face
the front of the engine.
(5) Install the lower bearing insert in the bearing
cap. The lower insert must be dry. Place strip of Plas-
tigage across full width of the lower insert at the cen-
ter of bearing cap. Plastigage must not crumble in
use. If brittle, obtain fresh stock.
(6) Install bearing cap and connecting rod on the
journal and tighten nuts to 45 N´m (33 ft. lbs.)
torque. DO NOT rotate crankshaft. Plastigage will
smear, resulting in inaccurate indication.
(7) Remove the bearing cap and determine amount
of bearing-to- journal clearance by measuring the
width of compressed Plastigage (Fig. 39).Plastigageshould indicate the same clearance across the
entire width of the insert. If the clearance var-
ies, it may be caused by either a tapered jour-
nal, bent connecting rod or foreign material
trapped between the insert and cap or rod.
(8) If the correct clearance is indicated, replace-
ment of the bearing inserts is not necessary. Remove
the Plastigage from crankshaft journal and bearing
insert. Proceed with installation.
(9) If bearing-to-journal clearance exceeds the
specification, install a pair of 0.0254 mm (0.001 inch)
undersize bearing inserts. All the odd size inserts
must be on the bottom. The sizes of the service
replacement bearing inserts are stamped on the
backs of the inserts. Measure the clearance as
described in the previous steps.
(10) The clearance is measured with a pair of
0.0254 mm (0.001 inch) undersize bearing inserts
installed. This will determine if two 0.0254 mm
(0.001 inch) undersize inserts or another combination
Fig. 36 Locking Tab Inspection
1 - ABNORMAL CONTACT AREA CAUSED BY LOCKING TABS
NOT FULLY SEATED OR BEING BENT
Fig. 37 Scoring Caused by Insufficient Lubrication
or Damaged Crankshaft Journal
Fig. 38 Rod and Piston Assembly Installation
Fig. 39 Measuring Bearing Clearance with
Plastigage
1 - PLASTIGAGE SCALE
2 - COMPRESSED PLASTIGAGE
9 - 34 ENGINE - 4.0LWJ
CONNECTING ROD BEARINGS (Continued)