2003 JEEP GRAND CHEROKEE Steering column

INSTRUMENT PANEL TRIM
BEZEL - PASSENGER
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 top pad from the instrument panel.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL TOP PAD - REMOVAL).
(3) From the underside of the top pad, remove the
four screws from the top of the passenger airbag door
that secure the passenger side trim bezel to the
instrument panel (Fig. 37).
(4) Remove the passenger side trim bezel from the
instrument panel top pad.
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) Position the passenger side trim bezel to the
instrument panel top pad.
(2) From the underside of the top pad, install and
tighten the four screws through the passenger airbag
door that secure the passenger side trim bezel to the
instrument panel (Fig. 37). Tighten the screws to
11.8 N´m (105 in. lbs.).
(3) Reinstall the top pad onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL TOP PAD - INSTALLA-
TION).
(4) Reconnect the battery negative cable.
Fig. 37 Instrument Panel Passenger Side Trim Bezel
Remove/Install
1 - INSTRUMENT PANEL AIRBAG DOOR REINFORCEMENT
2 - PASSENGER AIRBAG DOOR
3 - PASSENGER SIDE TRIM BEZEL SCREWS (4)
4 - INSTRUMENT PANEL TOP PAD
23 - 66 INSTRUMENT PANEL SYSTEMWJ

POWER OUTLET DOOR
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 center lower bezel from the instru-
ment panel. (Refer to 23 - BODY/INSTRUMENT
PANEL/IP CENTER BEZEL - LOWER - REMOVAL).
(3) With the power outlet door in the open posi-
tion, carefully spread the power outlet door hinge
arms far enough to disengage the pivot pins from the
pivots on the back side of the center lower bezel (Fig.
38).
NOTE: The power outlet door is more easily ser-
viced while in the open position. The illustration
shows the door in the closed position for improved
visibility of the assist spring orientation and anchor
point details.
(4) Disengage the stepped ends of the assist spring
from the anchor holes in the inboard power outlet
door hinge arm and in the side of the ash receiver
housing.
(5) Remove the power outlet door from the instru-
ment panel center lower bezel.
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) Position the power outlet door to the instru-
ment panel center lower bezel.
(2) Engage the stepped ends of the assist spring
with the anchor holes in the inboard power outlet
door hinge arm and in the side of the ash receiver
housing (Fig. 38).
(3) With the power outlet door in the open posi-
tion, carefully spread the power outlet door hinge
arms far enough to engage the pivot pins with the
pivots on the back side of the lower center bezel.
(4) Reinstall the center lower bezel into the instru-
ment panel. (Refer to 23 - BODY/INSTRUMENT
PANEL/IP CENTER BEZEL - LOWER - INSTALLA-
TION).
(5) Reconnect the battery negative cable.
Fig. 38 Instrument Panel Power Outlet Door
Remove/Install
1 - CENTER LOWER BEZEL
2 - ASH RECEIVER FLAME SHIELD
3 - ASH RECEIVER HOUSING
4 - PIVOT PINS
5 - ASSIST SPRING
6 - POWER OUTLET DOOR HINGE ARMS
WJINSTRUMENT PANEL SYSTEM 23 - 67

STEERING COLUMN OPENING
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) Remove the fuse cover from the Junction Block
(JB) and Body Control Module (BCM) unit under the
driver side outboard end of the instrument panel.
(Refer to 8 - ELECTRICAL/POWER DISTRIBU-
TION/FUSE COVER - REMOVAL).
(3) Remove the cluster bezel from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - REMOVAL).
(4) Remove the one screw that secures the out-
board end of the steering column opening cover to
the U-nut on the outboard end of the instrument
panel top pad (Fig. 39).
(5) Remove the two screws that secure the lower
edge of the steering column opening cover to the
U-nuts on the instrument panel steering column sup-
port bracket.
(6) Pull the steering column opening cover rear-
ward to disengage the three snap clips (one outboard
and two inboard) that secure it to the receptacles in
the instrument panel.
(7) Remove the steering column opening cover
from the instrument panel.
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. THISIS 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) Position the steering column opening cover
onto the instrument panel (Fig. 39).
(2) Align the three snap clips on the steering col-
umn opening cover with their receptacles in the
instrument panel.
(3) Using hand pressure, press firmly and evenly
on the steering column opening cover over the snap
clip locations until each of the snap clips is fully
engaged in its receptacle.
(4) Install and tighten the two screws that secure
the lower edge of the steering column opening cover
to the instrument panel steering column support
bracket. Tighten the screws to 2.2 N´m (20 in. lbs.).
(5) Install and tighten the one screw that secures
the outboard end of the steering column opening
cover to the U-nut on the outboard end of the instru-
ment panel top pad. Tighten the screw to 2.2 N´m (20
in. lbs.).
(6) Reinstall the cluster bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - INSTALLATION).
(7) Reinstall the fuse cover onto the Junction
Block (JB) and Body Control Module (BCM) unit
under the driver side outboard end of the instrument
panel. (Refer to 8 - ELECTRICAL/POWER DISTRI-
BUTION/FUSE COVER - INSTALLATION).
(8) Reconnect the battery negative cable.
Fig. 39 Steering Column Opening Cover Remove/
Install
1 - INSTRUMENT PANEL TOP PAD
2 - STEERING COLUMN OPENING COVER
3 - SCREW (3)
23 - 68 INSTRUMENT PANEL SYSTEMWJ

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)

REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Depress locking tab and unplug the wire har-
ness connector from the blower motor controller.
(3) Depress locking tab and unplug the controller
connector from the blower motor.
(4) Remove the 2 screws that secure the blower
motor controller to the HVAC housing.
(5) Remove the blower motor controller from the
HVAC housing (Fig. 15).
INSTALLATION
(1) Install the blower motor controller in the
HVAC housing. The housing is indexed to allow con-
troller mounting in only one position. Tighten the
mounting screws to 2.2 N´m (20 in. lbs.).
(2) Plug in the wire harness connector to the
blower motor controller.
(3) Plug in the connector from the blower motor
controller to the blower motor.
(4) Connect the battery negative cable.
BLOWER MOTOR RESISTOR
BLOCK
DESCRIPTION
Models with the standard manual temperature
control system have a blower motor resistor. The
blower motor resistor is mounted to the bottom of the
HVAC housing, under the instrument panel and just
inboard of the blower motor. It can be accessed for
service without removing any other components.
OPERATION
The resistor has multiple resistor wires, each of
which will reduce the current flow to the blower
motor to change the blower motor speed by changing
the resistance in the blower motor ground path. The
blower motor switch directs the ground path through
the correct resistor wire to obtain the selected speed.
With the blower motor switch in the lowest speed
position, the ground path for the motor is applied
through all of the resistor wires. Each higher speed
selected with the blower motor switch applies the
blower motor ground path through fewer of the resis-
tor wires, increasing the blower motor speed. When
the blower motor switch is in the highest speed posi-
tion, the blower motor resistor is bypassed and the
blower motor receives a direct path to ground.
The blower motor resistor cannot be repaired and,
if faulty or damaged, it must be replaced.
DIAGNOSIS AND TESTING - BLOWER MOTOR
RESISTOR BLOCK
For circuit descriptions and diagrams, refer to the
appropriate wiring information.
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) Unplug the wire harness connector from the
blower motor resistor.
Fig. 15 BLOWER MOTOR CONTROLLER REMOVE/
INSTALL
1 - BLOWER MOTOR CONTROLLER
2 - BLOWER MOTOR
3 - GROUND STRAP
4 - ELECTRICAL CONNECTORS
5 - HEATER CORE TUBES
WJCONTROLS 24 - 27
BLOWER MOTOR CONTROLLER (Continued)

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) Check for battery voltage at the fuse in the
Power Distribution Center (PDC). If OK, go to Step
2. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse.
(2) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the a/c heater control from the instrument
panel. (Refer to 24 - HEATING & AIR CONDITION-
ING/CONTROLS/A/C HEATER CONTROL -
REMOVAL) Check for continuity between the ground
circuit cavity of the a/c heater control wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 3. If not OK, repair the open
circuit to ground as required.
(3) With the a/c heater control wire harness con-
nector unplugged, place the a/c heater mode control
switch knob in any position except the Off position.
Check for continuity between the ground circuit ter-
minal and each of the blower motor driver circuit ter-
minals of the a/c heater control as you move the
blower motor switch knob to each of the four speed
positions. There should be continuity at each driver
circuit terminal in only one blower motor switch
speed position. If OK, test and repair the blower
driver circuits between the a/c heater control connec-
tor and the blower motor resistor as required. If not
OK, replace the faulty a/c heater control unit.
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 ACCIDENTALAIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
The blower motor switch cannot be adjusted or
repaired, and if faulty or damaged, the a/c heater
control must be replaced. (Refer to 24 - HEATING &
AIR CONDITIONING/CONTROLS/A/C HEATER
CONTROL - REMOVAL)
IN-CAR TEMPERATURE
SENSOR
DESCRIPTION
Models equipped with the optional Automatic Zone
Control (AZC) system use automatic dual zone tem-
perature control with infrared sensing technology.
The temperature sensor is located in the center
instrument panel, between the dual temperature
knobs of the AZC.
OPERATION
The Automatic Zone Control 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.
The infrared temperature sensor cannot be
adjusted or repaired and, if faulty or damaged, the
AZC head must be replaced.
NOTE: The infrared sensor window may be perma-
nently damaged if any type of cosmetic vinyl dress-
ings are allowed to contact the lens. Avoid spraying
or wiping this area with any cleaner or conditioner.
This may result in impaired temperature sensing
and control.
REMOVAL
The infrared temperature sensor cannot be
adjusted or repaired and, if faulty or damaged, the
AZC head must be replaced. (Refer to 24 - HEATING
& AIR CONDITIONING/CONTROLS/A/C HEATER
CONTROL - REMOVAL)
WJCONTROLS 24 - 29
BLOWER MOTOR SWITCH (Continued)