Round plug JEEP GRAND CHEROKEE 2002 WJ / 2.G Repair Manual

INSTRUMENT PANEL
STUCTURAL DUCT
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO MIN-
UTES FOR THE AIRBAG SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE 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 instrument panel from the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL -
REMOVAL).
(3) Place the instrument panel on a suitable work
surface. Be certain to take the proper precautions to
protect the instrument panel from any possible cos-
metic damage.
(4)
Remove all of the individual components that
remain secured to the instrument panel structural duct
as described elsewhere in this service information.
INSTALLATION
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) Reinstall all of the individual components that
were removed from the instrument panel structural
duct as described elsewhere in this service informa-
tion.
(2) Reinstall the instrument panel into the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL -
INSTALLATION).
(3) Reconnect the battery negative cable.
INSTRUMENT PANEL TOP
COVER
REMOVAL
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) Disconnect and isolate the battery negative
cable.
(2) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the rear edge (farthest
from the windshield) of the top cover up and away
from the instrument panel far enough to disengage
the four snap clip retainers from their receptacles in
the instrument panel top pad (Fig. 22).
(3) Remove the top cover from the top of the
instrument panel.
Fig. 22 Instrument Panel Top Cover Remove/Install
1 - ULTRA LIGHT SENSOR PLUG
2 - SEAL
3 - INSTRUMENT PANEL TOP COVER
WJINSTRUMENT PANEL SYSTEM 23 - 51

INSTALLATION
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) If the vehicle is not equipped with the optional
automatic headlamps light sensor/vehicle theft secu-
rity system indicator, be certain that the hole plug is
installed in the clearance hole located to the out-
board side of the driver side defroster outlet in the
instrument panel top cover (Fig. 22).
(2) Before installing the top cover onto the top of
the instrument panel, be certain that the rubber top
cover seal is properly positioned on the forward edge
of the top cover panel.
(3) Position the top cover onto the top of the
instrument panel.
(4) Align the four snap clips on the top cover with
the snap clip receptacles in the instrument panel top
pad.
(5) Press firmly downward on the top cover over
each of the four snap clip locations until each of the
snap clips is fully seated in their receptacles in the
instrument panel top pad.
(6) Reconnect the battery negative cable.
INSTRUMENT PANEL TOP PAD
REMOVAL
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) Disconnect and isolate the battery negative
cable.
(2) Remove the trim from the right and left A-pil-
lars. (Refer to 23 - BODY/INTERIOR/A-PILLAR
TRIM - REMOVAL).
(3) Remove the top cover from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL TOP COVER - REMOVAL).
(4) Remove the four nuts that secure the instru-
ment panel top pad to the studs on the dash panel
near the windshield fence line (Fig. 23).
(5) Remove the speakers from the instrument
panel top pad. (Refer to 8 - ELECTRICAL/AUDIO/
SPEAKER - REMOVAL - INSTRUMENT PANEL
SPEAKER).
(6) Disengage the retainer that secures each of the
two instrument panel wire harness speaker take outs
to the mounting hole in the instrument panel top
pad. Tuck the loose ends of these speaker take outs
down the defroster ducts to keep them out of the way
during the remainder of this procedure.
(7) If the vehicle is so equipped, remove the two
screws that secure the automatic headlamp light sen-
sor/vehicle theft security system indicator unit to the
instrument panel top pad just outboard of the driver
side defroster outlet. Move the sensor/indicator unit
towards the windshield to keep it out of the way dur-
ing the remainder of this procedure.
(8) Remove the cluster bezel from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - REMOVAL).
(9) Remove the instrument cluster from the instru-
ment panel. (Refer to 8 - ELECTRICAL/INSTRU-
MENT CLUSTER - REMOVAL).
(10) Remove the steering column opening cover
from the instrument panel. (Refer to 23 - BODY/IN-
STRUMENT PANEL/STEERING COLUMN OPEN-
ING COVER - REMOVAL).
(11) Roll the glove box down from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
GLOVE BOX - STANDARD PROCEDURE - GLOVE
BOX ROLL DOWN).
(12) Remove the end cap from the passenger side
lower outboard end of the instrument panel. (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL END CAP - REMOVAL).
(13) Remove the lower right center bezel from the
instrument panel. (Refer to 23 - BODY/INSTRU-
MENT PANEL/IP LOWER RIGHT CENTER BEZEL
- REMOVAL).
(14) Remove the glove box lamp and switch from
the instrument panel. (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - INTERIOR/GLOVE BOX
LAMP/SWITCH - REMOVAL).
23 - 52 INSTRUMENT PANEL SYSTEMWJ
INSTRUMENT PANEL TOP COVER (Continued)

INSTALLATION
(1) Position the seal on the door flange.
(2) Firmly press downward to seat seal on the door
flange.
(3)
Install the door trim panel (Refer to 23 - BODY/
DOOR - FRONT/TRIM PANEL - INSTALLATION).
FDR OUTER BELT
WEATHERSTRIP
REMOVAL
(1) Lower the door glass.
(2) Remove the screw from the inner door panel
attaching the seal to outer door panel (Fig. 4).
(3) Pull the seal rearward to release from the side
view mirror bezel.
(4) Lift seal and separate from door panel.
INSTALLATION
(1) Position seal on the door panel.
(2) Push the seal forward to install under the side
view mirror bezel.
(3) Install the screw from the inner door panel
attaching the seal to outer door panel.
(4) Raise the door glass.
FLIP-UP GLASS
WEATHERSTRIP
REMOVAL
(1) Raise flip up glass.
(2) Carefully pull the seal away from the flange
around the edge of the glass opening (Fig. 5).
(3) Remove it from the vehicle.
INSTALLATION
(1) Thoroughly clean the surface of the flange as
necessary.
(2) Align the weather strip seal with the window
opening corners.
(3) Firmly seat the seal around the entire flange.
But the seal ends together and smooth out any
remaining length.
(4)
Weatherstrip break should be 120mm left of latch
opening. Cut any surplus from non-plug end only.
FRONT DOOR 2ND
WEATHERSTRIP
REMOVAL
The front door secondary weatherstrip is attached
to the door shutface with push-in fasteners.(1) Open door.
(2) Using a trim panel removal tool, remove
push-in fasteners attaching secondary weatherstrip
to door shutface (Fig. 6).
(3) Separate secondary weatherstrip from door.
INSTALLATION
(1) Clean contact area as necessary.
(2) Position secondary weatherstrip on door shut-
face.
(3) Install push-in fasteners attaching secondary
weatherstrip to door shutface.
Fig. 5 Flip-up Glass Weatherstrip
1 - WEATHERSTRIP
2 - LIFTGATE W/FLIP-UP GLASS
Fig. 6 Front Door Secondary Weatherstrip
1 - SECONDARY WEATHERSTRIP
WJWEATHERSTRIP/SEALS 23 - 107
FRONT DOOR INNER BELT WEATHERSTRIP (Continued)

FRONT DOOR WEATHERSTRIP
REMOVAL
(1) Remove A-pillar trim (Refer to 23 - BODY/IN-
TERIOR/A-PILLAR TRIM - REMOVAL).
(2) Remove B-pillar upper trim (Refer to 23 -
BODY/INTERIOR/B-PILLAR UPPER TRIM -
REMOVAL).
(3) Remove B-pillar lower trim (Refer to 23 -
BODY/INTERIOR/B-PILLAR LOWER TRIM -
REMOVAL).
(4) Pull weatherstrip from door opening flange.
INSTALLATION
(1) Position weatherstrip at corners.
(2) Move upward and around edge of door opening
seating weatherstrip onto flange (Fig. 7).
(3) Engage connector plug with each end of weath-
erstrip at bottom of door opening.
(4) Install B-pillar lower trim (Refer to 23 - BODY/
INTERIOR/B-PILLAR LOWER TRIM - INSTALLA-
TION).
(5) Install B-pillar upper trim (Refer to 23 -
BODY/INTERIOR/B-PILLAR UPPER TRIM -
INSTALLATION).
(6) Install A-pillar trim (Refer to 23 - BODY/INTE-
RIOR/A-PILLAR TRIM - INSTALLATION).
HOOD SEAL
REMOVAL
(1) Raise hood.
(2) Pull hood seal from upper radiator crossmem-
ber.
(3) Separate seal from upper radiator crossmember
(Fig. 8).
INSTALLATION
(1) Position seal on upper radiator crossmember.
(2) Press seal onto upper radiator crossmember to
seat.
Fig. 7 Door Opening
1 - REAR DOOR OPENING WEATHERSTRIP
2 - FRONT DOOR OPENING WEATHERSTRIP
Fig. 8 Hood Seal
1 - HOOD SEAL
23 - 108 WEATHERSTRIP/SEALSWJ

LIFTGATE OPENING
WEATHERSTRIP
REMOVAL
(1) Pull seal away from flange around edge of lift-
gate opening.
(2) Separate weatherstrip from opening (Fig. 9).
(3) Clean weatherstrip flange as necessary.
INSTALLATION
(1) Position weatherstrip in opening with left end
of seal at opening centerline.
(2) Press weatherstrip onto flange in a clockwise
direction.
(3) Center and butt weatherstrip ends together at
centerline.
(4) If necessary, cut surplus from weatherstrip
(non-plug end only).
RDR INNER BELT
WEATHERSTRIP
REMOVAL
(1) Remove door trim panel (Refer to 23 - BODY/
DOORS - REAR/TRIM PANEL - REMOVAL).
(2) Using a trim stick, carefully pry rear inner
edge of inner belt weatherstrip upward.
(3) Grasp weatherstrip and pull upward to sepa-
rate from door flange (Fig. 10).
INSTALLATION
(1) Position weatherstrip on door flange.
(2) Firmly press downward to seat weatherstrip on
flange.
(3) Install trim panel (Refer to 23 - BODY/DOORS
- REAR/TRIM PANEL - INSTALLATION).
RDR OUTER BELT
WEATHERSTRIP
REMOVAL
(1) Remove trim panel (Refer to 23 - BODY/
DOORS - REAR/TRIM PANEL - REMOVAL).
(2) Using a small flat blade, disengage tangs
attaching outer belt weatherstrip to inner door panel.
(3) Lift weatherstrip upward and separate from
door (Fig. 10).
INSTALLATION
(1) Position the weatherstrip onto the door flange.
(2) Force the weatherstrip onto door flange and
engage tangs. Continue rearward until it is seated on
flange.
(3) Instal trim panel (Refer to 23 - BODY/DOORS
- REAR/TRIM PANEL - INSTALLATION).
Fig. 9 Liftgate Opening Weatherstrip
1 - LIFTGATE
2 - WEATHERSTRIP
Fig. 10 Rear Door Inner/Outer Belt Weatherstrip
1 - INNER BELT WEATHERSTRIP
2 - OUTER BELT WEATHERSTRIP
WJWEATHERSTRIP/SEALS 23 - 109

RDR SECONDARY
WEATHERSTRIP
REMOVAL
The rear door secondary weatherstrip is attached
to the door shutface with push-in fasteners.
(1) Open door.
(2) Using a trim panel removal tool, remove
push-in fasteners attaching secondary weatherstrip
to door shutface.
(3) Separate secondary weatherstrip from door
(Fig. 11).
INSTALLATION
(1) Clean contact area as necessary.
(2)
Position secondary weatherstrip on door shutface.
(3) Install push-in fasteners attaching secondary
weatherstrip to door shutface.
REAR DOOR WEATHERSTRIP
REMOVAL
(1) Remove C-pillar trim (Refer to 23 - BODY/IN-
TERIOR/C-PILLAR TRIM - REMOVAL).
(2) Remove B-pillar upper trim (Refer to 23 -
BODY/INTERIOR/B-PILLAR UPPER TRIM -
REMOVAL).
(3) Remove B-pillar lower trim(Refer to 23 -
BODY/INTERIOR/B-PILLAR LOWER TRIM -
REMOVAL).
(4) Remove screws at front of quarter trim panel.
(5) Pull weatherstrip from door opening flange.
INSTALLATION
(1) Position weatherstrip at corners.
(2) Move upward and around edge of door opening
seating weatherstrip onto flange (Fig. 7).(3) Engage connector plug with each end of weath-
erstrip at bottom of door opening.
(4) Install screws at front of quarter trim panel.
(5)
Install B-pillar lower trim (Refer to 23 - BODY/IN-
TERIOR/B-PILLAR LOWER TRIM - INSTALLATION).
(6) Install B-pillar upper trim (Refer to 23 -
BODY/INTERIOR/B-PILLAR UPPER TRIM -
INSTALLATION).
(7) Install C-pillar trim (Refer to 23 - BODY/INTE-
RIOR/C-PILLAR TRIM - INSTALLATION).
ROOF RAIL WEATHERSTRIP /
RETAINR
REMOVAL
(1) Open front and rear doors.
(2) Remove secondary seal from retainer to access
the screws holding the retainer to the A pillar and
roof panel.
(3) Remove the screws holding the retainer in
place (Fig. 12).
(4) Remove the retainer.
INSTALLATION
(1) Position the retainer on the A pillar and roof
panel.
(2) Align the screw holes and install the screws.
(3) Install secondary seal.
Fig. 11 Rear Door Secondary Weatherstrip
1 - SECONDARY WEATHERSTRIP
Fig. 12 Upper Body Seal With Retainer
1 - ROOF RAIL WEATHERSTRIP
2 - RETAINER
3 - SCREW
4 - BLOCKER
23 - 110 WEATHERSTRIP/SEALSWJ

DIAGNOSIS AND TESTING - HEATER
PERFORMANCE
Before performing the following tests, refer to Cool-
ing for the procedures to check the radiator coolant
level, serpentine drive belt tension, radiator air flow
and the radiator fan operation. Also be certain that
the accessory vacuum supply line is connected at the
engine intake manifold for the manual temperature
control system.
MAXIMUM HEATER OUTPUT
Engine coolant is delivered to the heater core
through two heater hoses. With the engine idling at
normal operating temperature, set the temperature
control knob in the full hot position, the mode control
switch knob in the floor heat position, and the blower
motor switch knob in the highest speed position.
Using a test thermometer, check the temperature of
the air being discharged at the HVAC housing floor
outlets. Compare the test thermometer reading to the
Temperature Reference chart.
Temperature Reference
Ambient Air Temperature15.5É C
(60É F)21.1É C
(70É F)26.6É C
(80É F)32.2É C
(90É F)
Minimum Air Temperature at
Floor Outlet62.2É C
(144É F)63.8É C
(147É F)65.5É C
(150É F)67.2É C
(153É F)
If the floor outlet air temperature is too low, refer
to Cooling to check the engine coolant temperature
specifications. Both of the heater hoses should be hot
to the touch. The coolant return heater hose should
be slightly cooler than the coolant supply heater
hose. If the return hose is much cooler than the sup-
ply hose, locate and repair the engine coolant flow
obstruction in the cooling system. Refer to Cooling
for the procedures.
OBSTRUCTED COOLANT FLOW
Possible locations or causes of obstructed coolant
flow:
²Pinched or kinked heater hoses.
²Improper heater hose routing.
²Plugged heater hoses or supply and return ports
at the cooling system connections.
²A plugged heater core.
If proper coolant flow through the cooling system is
verified, and heater outlet air temperature is still
low, a mechanical problem may exist.
MECHANICAL PROBLEMS
Possible locations or causes of insufficient heat:
²An obstructed cowl air intake.
²Obstructed heater system outlets.
²A blend door not functioning properly.
TEMPERATURE CONTROL
If the heater outlet air temperature cannot be
adjusted with the temperature control knob(s) on the
A/C Heater control panel, the following could require
service:
²The A/C heater control.
²The blend door actuator(s).
²The wire harness circuits for the A/C heater con-
trol or the blend door actuator(s).²The blend door(s).
²Improper engine coolant temperature.
STANDARD PROCEDURE - DIODE
REPLACEMENT
(1) Disconnect and isolate the negative battery
cable.
(2) Locate the diode in the harness, and remove
the protective covering.
(3) Remove the diode from the harness, pay atten-
tion to the current flow direction (Fig. 3).
(4) Remove the insulation from the wires in the
harness. Only remove enough insulation to solder in
the new diode.
Fig. 3 DIODE IDENTIFICATION
1 - CURRENT FLOW
2 - BAND AROUND DIODE INDICATES CURRENT FLOW
3 - DIODE AS SHOWN IN THE DIAGRAMS
24 - 6 HEATING & AIR CONDITIONINGWJ
HEATING & AIR CONDITIONING (Continued)

LOCATING VACUUM LEAKS
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 AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect the vacuum harness connector from
the back of the A/C Heater mode control switch on
the control panel.
(2) Connect the test set vacuum hose probe to each
port in the vacuum harness connector, one at a time,
and pause after each connection (Fig. 2). The test set
gauge should return to the 27 kPa (8 in. Hg.) setting
shortly after each connection is made. If OK, replace
the faulty mode control switch. If not OK, go to Step
3.(3) Determine the vacuum line color of the vacuum
circuit that is leaking. To determine the vacuum line
colors, refer to the Vacuum Circuits chart (Fig. 3).
(4) Disconnect and plug the vacuum line from the
component (fitting, actuator, valve, switch, or reser-
voir) on the other end of the leaking circuit. Instru-
ment panel disassembly or removal may be necessary
to gain access to some components.
(5) Connect the test set hose or probe to the open
end of the leaking circuit. The test set gauge should
return to the 27 kPa (8 in. Hg.) setting shortly after
each connection is made. If OK, replace the faulty
disconnected component. If not OK, go to Step 6.
(6) To locate a leak in a vacuum line, leave one
end of the line plugged and connect the test set hose
or probe to the other end. Run your fingers slowly
along the line while watching the test set gauge. The
vacuum reading will fluctuate when your fingers con-
tact the source of the leak. To repair the vacuum
line, cut out the leaking section of the line. Then,
insert the loose ends of the line into a suitable length
of 3 millimeter (1/8-inch) inside diameter rubber
hose.
Fig. 2 VACUUM CIRCUIT TEST
WJCONTROLS 24 - 11
CONTROLS (Continued)

open circuit to the fuse in the junction block as
required.
(5) The coil ground terminal cavity (85) is switched
to ground through the Powertrain Control Module
(PCM). There should be continuity between this cav-
ity and the A/C compressor clutch relay control cir-
cuit cavity of the PCM wire harness connector C
(gray) at all times. If not OK, repair the open circuit
as required.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Power Distribution
Center (PDC) (Fig. 11).
(3) Refer to the label on the PDC for compressor
clutch relay identification and location.
(4) Unplug the compressor clutch relay from the
PDC.
INSTALLATION
(1) Install the compressor clutch relay by aligning
the relay terminals with the cavities in the PDC and
pushing the relay firmly into place.
(2) Install the PDC cover.
(3) Connect the battery negative cable.
(4) Test the relay operation.
A/C HEATER CONTROL
DESCRIPTION
The manual temperature control HVAC system
uses a combination of electrical, and vacuum con-trols. The Automatic Zone Control (AZC) HVAC sys-
tem uses only electrical controls. These controls
provide the vehicle operator with a number of setting
options to help control the climate and comfort
within the vehicle. Refer to the owner's manual in
the vehicle glove box for more information on the
suggested operation and use of these controls.
Both a/c heater control panels are located on the
instrument panel inboard of the steering column and
below the radio (Fig. 12). Both control panels contain
rotary-type temperature control knob(s), a rotary-
type mode control switch knob, a rotary-type blower
motor speed switch knob and an air conditioning
compressor push button switch. The rear window
defogger push button switch is also located on a/c
heater control panel. The AZC control panel also fea-
tures a recirculation push button switch and a vac-
uum fluorescent display area.
OPERATION
The AZC control module uses infrared sensing
technology to control occupant comfort levels, not the
actual passenger compartment air temperature. Dual
infrared sensors mounted in the face of the control
unit independently measure the surface temperature
to maintain customer-perceived comfort temperature
under changing conditions. Dual Zone temperature
control provides wide side-to-side variation in comfort
temperature to exceed the needs of either front seat
occupant. This sensing system replaces interior air
temperature and solar sensors used to approximate
direct sensing control through complex control pro-
grams.
Fig. 11 POWER DISTRIBUTION CENTER (PDC)
1 - TRANSMISSION CONTROL MODULE (TCM)
2 - NEGATIVE CABLE
3 - POSITIVE CABLE
4 - POWER DISTRIBUTION CENTER (PDC)
Fig. 12 A/C HEATER CONTROL PANELS
WJCONTROLS 24 - 17
A/C COMPRESSOR CLUTCH RELAY (Continued)

AIR INLET POINTER
63 Engine Intake Air Temperature
(in degrees F)-40 to
215
64 Vehicle speed in MPH 0 to 255
65 Engine RPM/100 -0 to 82
66 Engine Coolant Temp - 40 (in
degrees F)-40 to
215
67 Country Code 0 to 255
68 Not used 0 to 0
69 Not used 0 to 0
IR SENSOR POINTER
Pointer
NumberDESCRIPTION Value
Displayed
70 Thermistor temp (in degrees) -40 to
215
71 Left side sensor A/D (filtered) 0 to 255
72 Right side sensor A/D (filtered) 0 to 255
73 Left side temp (in degrees F) -40 to
140
74 Right side temp (in degrees F) -40 to
140
75 Not used 0 to 0
76 Not used 0 to 0
77 Not used 0 to 0
78 Not used 0 to 0
79 Not used 0 to 0
IDENTIFICATION POINTER
Pointer
NumberDESCRIPTION Value
Displayed
80 ROM bit pattern number (digits
1,2,3 & 4)0to
9999
81 ROM bit pattern number (digits
5,6,7 & 8)0to
9999
82 CAL bit pattern number (digits
1,2,3 & 4)0to
9999
83 CAL bit pattern number (digits
5,6,7 & 8)0to
9999
84 Not used 0 to 0
85 Not used 0 to 0
86 Not used 0 to 0
87 Not used 0 to 0
88 Not used 0 to 0
89 Not used 0 to 0
OUTPUT CIRCUIT/ACTUATOR TESTS
In the Output Circuit/Actuator Test mode, the out-
put circuits can be viewed, monitored, overridden,
and tested. If a failure occurs in an output circuit,
test the circuit by overriding the system. Test the
actuator through its full range of operation.
(1) To begin the Output Circuit/Actuator Tests you
must be in the Select Test mode.
(2) With a ª00º value displayed in the Test Selector
and no stick man, turn the rotary temperature con-
trol knob until the test number you are looking for
appears in the Test Selector display. See the Circuit
Testing charts for a listing of the test numbers, test
items, test types, system tested, and displayed val-
ues.
(3) To see the output value, depress the a/c or
recirc button. The values displayed will represent the
output from the AZC control module.
(4) To enter the actuator test, depress the a/c or
recirc button. Then, rotate the right temperature set
knob to the desired position.
REMOVAL
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 AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the center upper, and center lower
bezels from the instrument panel. Refer to Instru-
ment Panel System for the procedures.
(3) Remove the 4 screws that secure the a/c heater
control to the instrument panel (Fig. 13).
(4) Pull the a/c heater control assembly away from
the instrument panel far enough to access the con-
nections on the back of the control.
(5) Unplug the wire and/or vacuum harness con-
nectors from the back of the a/c heater control (Fig.
14).
(6) Remove the a/c heater control from the instru-
ment panel.
24 - 24 CONTROLSWJ
A/C HEATER CONTROL (Continued)