2002 DODGE RAM instrument panel

instrument panel just inboard of the glove box. Vehi-
cles equipped with a manual transmission have a
lighted storage bin installed on the instrument panel
in place of the fold-down cup holder.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT 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 DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Position the storage bin unit onto the instru-
ment panel (Fig. 10).
(2) Engage the illumination lamp and hood
retainer clip to the back of the instrument panel stor-
age bin unit.
(3) Raise and position the top of the storage bin to
the instrument panel.
(4) Install and tighten the two screws that secure
the top of the storage bin unit to the instrument
panel. Tighten the screws to 2.2 N´m (20 in. lbs.).
(5) Reinstall the cluster bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - INSTALLATION).
(6) Reconnect the battery negative cable.
INSTRUMENT PANEL
ASSEMBLY
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN,
SEAT BELT TENSIONER, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT
AND ISOLATE THE BATTERY NEGATIVE (GROUND)
CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG
SYSTEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS
THE ONLY SURE WAY TO DISABLE THE AIRBAG SYS-
TEM. FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT AND POSSIBLE PERSONAL INJURY.
NOTE: Before starting this procedure, be certain to
turn the steering wheel until the front wheels are in
the straight-ahead position.
(1)
Disconnect and isolate the battery negative cable.
(2) Remove the Airbag Control Module (ACM) and
bracket from the floor panel transmission tunnel.
(Refer to 8 - ELECTRICAL/RESTRAINTS/AIRBAG
CONTROL MODULE - REMOVAL).
(3) Remove the trim from the left and right cowl
side inner panels. (Refer to 23 - BODY/INTERIOR/
COWL TRIM COVER - REMOVAL).
(4) Remove the steering column opening cover
from the instrument panel. (Refer to 23 - BODY/IN-
STRUMENT PANEL/STEERING COLUMN OPEN-
ING COVER - REMOVAL).
(5)
Remove the two screws that secure the inside
hood latch release handle to the instrument panel lower
reinforcement and lower the release handle to the floor.
(6)Disconnect the clockspring pigtail wire connector
from the instrument panel wire harness connector
located on the instrument panel lower reinforcement.
(7) If the vehicle is so equipped, disconnect the
overdrive lockout switch pigtail wire connector from
the instrument panel wire harness connector near
the instrument panel lower reinforcement.
(8) Remove the steering column from the vehicle,
but do not remove the driver airbag, the steering
wheel, or the switches from the column. Be certain
that the steering wheel is locked and secured from
rotation to prevent the loss of clockspring centering.
(Refer to 19 - STEERING/COLUMN - REMOVAL).
(9) From under the driver side of the instrument
panel, perform the following:
(a) Disengage the park brake release handle
linkage rod from the park brake mechanism on the
Fig. 10 Instrument Panel Storage Bin Remove/Install
1 - SCREWS
2 - STORAGE BIN (RAISED)
3 - STORAGE BIN (LOWERED)
BR/BEINSTRUMENT PANEL SYSTEM 23 - 115
STORAGE BIN (Continued)

left cowl side inner panel. (Refer to 5 - BRAKES/
PARKING BRAKE/RELEASE - REMOVAL).
(b) Disconnect the instrument panel wire har-
ness connector from the park brake switch on the
park brake mechanism.
(c) Disconnect the three connectors (one from the
body wire harness, and two from the headlamp and
dash wire harness) from the three connector recep-
tacles located closest to the dash panel on the back
of the Junction Block (JB).
(d) Remove the screw from the center of the
headlamp and dash wire harness to instrument
panel wire harness bulkhead connector and discon-
nect the connector.
(e) Disconnect the instrument panel wire har-
ness to door wire harness connector located directly
below the instrument panel wire harness to head-
lamp and dash wire harness bulkhead connector.
(f) If the vehicle is equipped with the Infinity
sound system option, disconnect the Infinity wire
harness connector from the instrument panel wire
harness connector that is secured to the outboard
side of the instrument panel wire harness to head-
lamp and dash wire harness bulkhead connector.(g) Disconnect the instrument panel wire har-
ness connector from the stop lamp switch.
(h) Disconnect the heater-A/C housing vacuum
harness connector from the heater-A/C control vac-
uum harness connector located near the left end of
the heater-A/C housing.
(10) From under the passenger side of the instru-
ment panel, disconnect the two halves of the radio
antenna coaxial cable connector.
(11) Loosen the right and left instrument panel
cowl side roll-down bracket screws about 13 mm
(0.50 inch) (Fig. 11).
(12) Remove the five screws that secure the top of
the instrument panel to the top of the dash panel,
removing the center screw last.
(13) Roll down the instrument panel and install a
temporary hook in the center hole on top of the
instrument panel. Secure the other end of the hook
to the center hole in the top of the dash panel. The
hook should support the instrument panel in its
rolled down position about 46 cm (18 inches) from
the dash panel.
(14) With the instrument panel supported in the
roll-down position, disconnect the instrument panel
Fig. 11 Instrument Panel Assembly Remove/Install
1 - PLASTIC NUT
2 - SCREWS3 - SCREWS
23 - 116 INSTRUMENT PANEL SYSTEMBR/BE
INSTRUMENT PANEL ASSEMBLY (Continued)

wire harness connectors from the heater-A/C housing
wire harness connectors.
(15) With the aid of an assistant, remove the tem-
porary hook and lift the instrument panel assembly
off of the roll-down bracket screws and remove it
from the vehicle.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN,
SEAT BELT TENSIONER, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT
AND ISOLATE THE BATTERY NEGATIVE (GROUND)
CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG
SYSTEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS
THE ONLY SURE WAY TO DISABLE THE AIRBAG SYS-
TEM. FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT AND POSSIBLE PERSONAL INJURY.
(1)With the aid of an assistant, load the instrument
panel assembly onto the roll-down bracket screws on
the cowl side inner panels in the vehicle (Fig. 11).
Install a temporary hook in the center hole on top of the
instrument panel. Secure the other end of the hook to
the center hole in the top of the dash panel. The hook
should support the instrument panel in its rolled down
position about 46 cm (18 inches) from the dash panel.
(2) With the instrument panel supported in the
roll-down position, reconnect the instrument panel
wire harness connectors to the heater-A/C housing
wire harness connectors.
(3) Remove the temporary hook from the instru-
ment panel and roll the instrument panel up to its
installed position against the dash panel.
(4) Install and tighten the five screws that secure
the top of the instrument panel to the top of the dash
panel. Tighten the screws to 3.2 N´m (28 in. lbs.).
(5) Tighten the right and left instrument panel
cowl side roll-down bracket screws. Tighten the
screws to 11.9 N´m (105 in. lbs.).
(6) From under the passenger side of the instru-
ment panel, reconnect the two halves of the radio
antenna coaxial cable connector.
(7) From under the driver side of the instrument
panel, perform the following:
(a) Engage the park brake release handle link-
age rod with the park brake mechanism on the left
cowl side inner panel. (Refer to 5 - BRAKES/PARK-
ING BRAKE/RELEASE - INSTALLATION).
(b) Reconnect the instrument panel wire harness
connector to the park brake switch on the park
brake mechanism.(c) Reconnect the three connectors (one from the
body wire harness, and two from the headlamp and
dash wire harness) to the three connector recepta-
cles located closest to the dash panel on the back of
the Junction Block (JB).
(d)
Reconnect the headlamp and dash wire harness
to instrument panel wire harness bulkhead connector
and tighten the screw in the center of the connector.
Tighten the screw to 3.5 N´m (31 in. lbs.).
(e) Reconnect the instrument panel wire harness
to door wire harness connector located directly
below the instrument panel wire harness to head-
lamp and dash wire harness bulkhead connector.
(f) If the vehicle is equipped with the Infinity
sound system option, reconnect the Infinity wire
harness connector to the instrument panel wire
harness connector that is secured to the outboard
side of the instrument panel wire harness to head-
lamp and dash wire harness bulkhead connector.
(g) Reconnect the instrument panel wire harness
connector to the stop lamp switch.
(h) Reconnect the heater-A/C housing vacuum
harness connector to the heater-A/C control vac-
uum harness connector located near the left end of
the heater-A/C housing.
(8) Reinstall the steering column into the vehicle.
Be certain that the steering wheel was locked and
secured from rotation to prevent the loss of clock-
spring centering. (Refer to 19 - STEERING/COL-
UMN - INSTALLATION).
(9) If the vehicle is so equipped, reconnect the
overdrive lockout switch pigtail wire connector to the
instrument panel wire harness connector near the
instrument panel lower reinforcement.
(10) Reconnect the clockspring pigtail wire connec-
tor to the instrument panel wire harness connector
at the instrument panel lower reinforcement.
(11) Position the inside hood latch release handle
to the instrument panel lower reinforcement.
(12) Install and tighten the two screws that secure
the inside hood latch release handle to the instru-
ment panel lower reinforcement. Tighten the screws
to 2.8 N´m (25 in. lbs.).
(13) Reinstall the steering column opening cover
onto the instrument panel. (Refer to 23 - BODY/IN-
STRUMENT PANEL/STEERING COLUMN OPEN-
ING COVER - INSTALLATION).
(14) Reinstall the trim onto the left and right cowl
side inner panels. (Refer to 23 - BODY/INTERIOR/
COWL TRIM COVER - INSTALLATION).
(15) Reinstall the Airbag Control Module (ACM)
and bracket onto the floor panel transmission tunnel.
(Refer to 8 - ELECTRICAL/RESTRAINTS/AIRBAG
CONTROL MODULE - INSTALLATION).
(16) Reconnect the battery negative cable.
BR/BEINSTRUMENT PANEL SYSTEM 23 - 117
INSTRUMENT PANEL ASSEMBLY (Continued)

HEATING & AIR CONDITIONING
TABLE OF CONTENTS
page page
HEATING & AIR CONDITIONING
DESCRIPTION...........................1
OPERATION.............................1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - A/C
PERFORMANCE........................2
DIAGNOSIS AND TESTING - HEATER
PERFORMANCE........................6STANDARD PROCEDURE
STANDARD PROCEDURE - DIODE
REPLACEMENT.........................7
SPECIFICATIONS.........................7
CONTROLS.............................9
DISTRIBUTION..........................30
PLUMBING.............................40
HEATING & AIR
CONDITIONING
DESCRIPTION - HEATER AND AIR
CONDITIONER
All vehicles are equipped with a common HVAC
housing assembly (Fig. 1). The system combines air
conditioning, heating, and ventilating capabilities in
a single unit housing mounted under the instrument
panel. On heater-only systems, the evaporator coil
and recirculation door are omitted from the housing.
DESCRIPTION - COOLING SYSTEM
REQUIREMENTS
To maintain the performance level of the HVAC
system, the engine cooling system must be properly
maintained. The use of a bug screen is not recom-
mended. Any obstructions in front of the radiator orcondenser will reduce the performance of the air con-
ditioning and engine cooling systems.
The engine cooling system includes the heater core
and the heater hoses. Refer to Engine Cooling for
more information before the opening of, or attempt-
ing any service to the engine cooling system.
DESCRIPTION - REFRIGERANT SYSTEM
SERVICE PORT
The two refrigerant system service ports are used
to charge, recover/recycle, evacuate, and test the air
conditioning refrigerant system. Unique service port
coupler sizes are used on the R-134a system, to
ensure that the refrigerant system is not accidentally
contaminated by the use of the wrong refrigerant
(R-12), or refrigerant system service equipment.
OPERATION - HEATER AND AIR CONDITIONER
The heater and optional air conditioner are blend-
air type systems. In a blend-air system, a blend door
controls the amount of unconditioned air (or cooled
air from the evaporator on models with air condition-
ing) that is allowed to flow through, or around, the
heater core. A temperature control knob on the A/C
Heater control panel determines the discharge air
temperature by controlling an electric actuator,
which moves the blend door. This allows an almost
immediate control of the output air temperature of
the system.
The mode control knob on the heater-only or A/C
Heater control panel is used to direct the conditioned
air to the selected system outlets. Both mode control
switches use engine vacuum to control the mode
doors, which are operated by vacuum actuators.
On air conditioned vehicles, the outside air intake
can be shut off by selecting the Recirculation Mode
with the mode control knob. This will operate a vac-
uum actuated recirculation door that closes off the
outside fresh air intake and recirculates the air that
is already inside the vehicle.
Fig. 1 COMMON BLEND-AIR HEATER-AIR
1 - HEATER CORE
2 - BLEND DOOR
3 - EVAPORATOR (A/C ONLY)
4 - RECIRCULATION DOOR (A/C ONLY)
5 - FLOOR/PANEL DOOR
6 - FLOOR/DEFROST DOOR
BR/BEHEATING & AIR CONDITIONING 24 - 1

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
located between the a/c heater control and the HVAC
housing under the instrument panel.
(2) Connect the test set vacuum hose probe to each
port in the HVAC housing half of the vacuum har-
ness connector, one port 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 a/c
heater control. If not OK, go to step Step 3.(3) Determine the vacuum line color of the vacuum
circuit that is leaking. To determine the vacuum line
colors, see 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. Refer to Instru-
ment Panel System for the procedures.
(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 of the line. Run your fin-
gers slowly along the line while watching the test set
gauge. The vacuum reading will fluctuate when your
fingers contact 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 (0.125 inch) inside diameter
rubber hose.
A/C COMPRESSOR CLUTCH
DESCRIPTION
The compressor clutch assembly consists of a sta-
tionary electromagnetic coil, a hub bearing and pul-
ley assembly, and a clutch plate (Fig. 4). The
electromagnetic coil unit and the hub bearing and
pulley assembly are each retained on the nose of the
compressor front housing with snap rings. The clutch
plate is mounted to the compressor shaft and secured
with a nut.
Fig. 2 VACUUM CIRCUIT TEST
BR/BECONTROLS 24 - 11
CONTROLS (Continued)

(1) The relay common feed terminal cavity (30) is
connected to fused battery feed. There should be bat-
tery voltage at the cavity for relay terminal 30 at all
times. If OK, go to Step 2. If not OK, repair the open
circuit to the fuse in the PDC as required.
(2) The relay normally closed terminal (87A) is not
used in this application. Go to Step 3.
(3) The relay normally open terminal cavity (87) is
connected to the compressor clutch coil. There should
be continuity between this cavity and the A/C com-
pressor clutch relay output circuit cavity of the com-
pressor clutch coil wire harness connector. If OK, go
to Step 4. If not OK, repair the open circuit as
required.
(4) The relay coil battery terminal (86) is con-
nected to the fused ignition switch output (run/start)
circuit. There should be battery voltage at the cavity
for relay terminal 86 with the ignition switch in the
On position. If OK, go to Step 5. If not OK, repair the
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. 17).
(3) Refer to the label on the PDC for compressor
clutch relay identification and location.(4) Unplug the compressor clutch relay from the
PDC and remove it.
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
Both the heater-only and a/c heater systems use a
combination of electrical and vacuum 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 man-
ual in the vehicle glove box for more information on
the features, use, and suggested operation of these
controls.
OPERATION
The heater-only or a/c heater control panel is
located to the right of the instrument cluster on the
instrument panel. The control panel contains a rota-
ry-type temperature control knob, a rotary-type mode
control switch knob, and a rotary-type blower motor
speed switch knob. On models with the optional
heated mirror system, a momentary push button
switch and indicator lamp are located near the bot-
tom of the a/c heater control panel. Refer to Heated
Mirrors for more information on this feature.
The heater-only or a/c heater control panel cannot
be repaired. If faulty or damaged, the entire unit
must be replaced. The control knobs and the illumi-
nation lamps are available for service replacement.
DIAGNOSIS AND TESTING - A/C HEATER
CONTROL
Satisfactory heater and air conditioner perfor-
mance depends upon proper operation and adjust-
ment of all operating controls and refrigeration
system components. For circuit descriptions and dia-
grams, (Refer to Appropriate Wiring Information).
These inspections, tests, and adjustments should be
used to locate the cause of a malfunction.
Operation must be tested as described in the fol-
lowing sequence:
(1) Inspect and adjust the serpentine drive bel-
t(Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE
BELTS - DIAGNOSIS AND TESTING).
(2) Start the engine and hold the idle speed at
1,300 rpm.
Fig. 17 POWER DISTRIBUTION CENTER
1 - COVER
2 - POWER DISTRIBUTION CENTER
24 - 18 CONTROLSBR/BE
A/C COMPRESSOR CLUTCH RELAY (Continued)

(3) On vehicles with air conditioning, turn the
temperature control knob to the extreme counter
clockwise (Cool) position, and set the mode control
switch knob to the Bi-Level (A/C) position. The out-
side (recirculation) air door should be open to outside
air. If not OK, (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS - DIAGNOSIS AND TEST-
ING - VACUUM SYSTEM).
(4) Open the vehicle windows. Test the blower
motor operation in all speeds. If not OK, (Refer to 24
- HEATING & AIR CONDITIONING/DISTRIBU-
TION/BLOWER MOTOR - DIAGNOSIS AND TEST-
ING).
(5) On vehicles with air conditioning, the compres-
sor should be running and the air conditioning sys-
tem in operation unless the ambient air temperature
is below about -1É C (30É F). If not OK, (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - A/C PERFORMANCE).
(6) Check the mode control switch operation. The
heater and air conditioner systems should respond as
described in the owner's manual in the vehicle glove
box to each mode selected. Reduce the engine speed
to normal idle. The vacuum will be high at low idle
and the vacuum actuators should respond quickly. If
not OK, (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - DIAGNOSIS AND TEST-
ING - VACUUM SYSTEM).
(7) If the vacuum tests, and the electrical compo-
nent and circuit tests reveal no problems, disassem-
ble the HVAC housing to inspect for mechanical
misalignment or binding of the mode doors (Refer to
24 - HEATING & AIR CONDITIONING/DISTRIBU-
TION/HVAC HOUSING - DISASSEMBLY)
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) Reach under the instrument panel near the
driver side of the floor panel transmission tunnel andunplug the a/c heater control to HVAC housing vac-
uum harness connector.
(3) While still reaching under the instrument
panel, disengage the retainer on the a/c heater con-
trol half of the vacuum harness from the hole in the
center distribution duct (Fig. 18).
(4) Remove the cluster bezel from the instrument
panel(Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - REMOVAL).
(5) Remove the four screws that secure the a/c
heater control to the instrument panel (Fig. 19).
(6) 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.
(7) Unplug the wire harness connector from the
back of the a/c heater control.
(8) On vehicles with heated mirrors, unplug the
heated mirror wire harness connector from the back
of the a/c heater control.
(9) Remove the a/c heater control from the instru-
ment panel.
INSTALLATION
(1) Plug the wire harness connector(s) into the
receptacle(s) on the back of the a/c heater control.
(2) Route the HVAC vacuum harness through the
hole in the reinforcement below the a/c heater control
opening of the instrument panel.
(3) Position the a/c heater control in the instru-
ment panel and secure it with four screws. Tighten
the screws to 2.2 N´m (20 in. lbs.).
Fig. 18 A/C HEATER CONTROL VACUUM HARNESS
ROUTING
1 - A/C HEATER CONTROL VACUUM HARNESS
2 - REINFORCEMENT
3 - RETAINER
4 - CENTER DISTRIBUTION DUCT
BR/BECONTROLS 24 - 19
A/C-HEATER CONTROL (Continued)

(4) Reinstall the cluster bezel to the instrument
panel(Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - INSTALLATION).
(5) Reach under the instrument panel to reinstall
the a/c heater control vacuum harness retainer to the
side of the center distribution duct.
(6) Plug in the two halves of the a/c heater control
to HVAC housing vacuum harness connector.
(7) Connect the battery negative cable.
A/C HIGH PRESSURE SWITCH
DESCRIPTION
The a/c high pressure switch is located on the dis-
charge line near the compressor. The switch is
screwed onto a fitting that contains a Schrader-type
valve, which allows the switch to be serviced without
discharging the refrigerant system. The discharge
line fitting is equipped with an O-ring to seal the
switch connection.
OPERATION
The a/c high pressure switch is connected in series
electrically with the a/c low pressure switch between
ground and the Powertrain Control Module (PCM).
The switch contacts open and close causing the PCM
to turn the compressor clutch on and off. This pre-
vents compressor operation when the discharge line
pressure approaches high levels.
The a/c high pressure switch contacts are open
when the discharge line pressure rises above about3100 to 3375 kPa (450 to 490 psi). The switch con-
tacts will close when the discharge line pressure
drops to about 1860 to 2275 kPa (270 to 330 psi).
When checking refrigerant system pressures with a
manifold gauge set, keep in mind that the indicated
pressures will be about 172 kpa (25 psi) below the
actual switch pressure values due to the pressure
drop that occurs in the refrigerant system between
the switch and the high pressure service port.
The a/c high pressure switch is a factory-calibrated
unit. The switch cannot be adjusted or repaired and,
if faulty or damaged, it must be replaced.
DIAGNOSIS AND TESTING - A/C HIGH
PRESSURE SWITCH
Before performing diagnosis of the a/c high pres-
sure switch, verify that the refrigerant system has
the correct refrigerant charge. (Refer to 24 - HEAT-
ING & AIR CONDITIONING - DIAGNOSIS AND
TESTING)
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the a/c high pressure switch wire har-
ness connector from the switch on the refrigerant
system fitting.
(3) On the four terminal high pressure switch,
check for continuity between terminals C and D. On
the two terminal switch, check for continuity
between both terminals of the a/c high pressure
switch. There should be continuity. If OK, test and
repair the A/C switch sense circuit as required. If not
OK, replace the faulty switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the a/c
high pressure switch, which is mounted to a fitting
on the discharge line between the compressor and
the condenser inlet.
(3) Unscrew the a/c high pressure switch from the
discharge line fitting.
(4) Remove the a/c high pressure switch from the
vehicle.
(5) Remove the O-ring seal from the discharge line
fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the discharge line fitting.
Use only the specified O-rings as they are made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the com-
pressor in the vehicle. (Refer to 24 - HEATING &
Fig. 19 A/C HEATER CONTROL REMOVE/INSTALL
1 - HEATED MIRROR WIRE HARNESS CONNECTOR
2 - WIRE HARNESS CONNECTOR
3 - SCREW
4 - HEATER-A/C CONTROL
24 - 20 CONTROLSBR/BE
A/C-HEATER CONTROL (Continued)