steering CHRYSLER VOYAGER 2004 Service Manual

system, the center outlet of the three has fixed vanes
and also houses the remote front infrared tempera-
ture sensors.
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 negative battery
cable.
(2) Remove the center bezel from the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL -
REMOVAL).
(3) Place the center bezel face down on a suitable
work surface. Be certain to take the proper precau-
tions to protect the face of the center bezel from cos-
metic damage.
(4) If the vehicle is equipped with the optional
ATC system, disconnect the ATC remote infrared
temperature sensor jumper harness from the sensor
connector receptacle located on the bottom of the cen-
ter outlet housing (Fig. 3).(5) Remove the three screws that secure the bot-
tom of the outlet housing to the center bezel.
(6) Roll the bottom of the outlet housing upwards
towards the top of the center bezel far enough to dis-
engage the retainer features on the top of the outlet
housing from their receptacles at the top of the cen-
ter bezel.
(7) Remove the center bezel outlets and housing
from the center bezel as a unit.
REMOVAL - DEMISTER OUTLET
(1) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the outer perimeter of the
demister outlet away from the instrument panel top
pad until the snap features on the outlet are released
(Fig. 4).
(2) Remove the demister outlet from the demister
duct opening in the instrument panel top pad.
REMOVAL - INSTRUMENT PANEL OUTLET
(1) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the outer perimeter of the
instrument panel outlet away from the instrument
panel top pad until the snap features on the outlet
are released (Fig. 5).
(2) Remove the instrument panel outlet from the
panel duct opening in the instrument panel top pad.
INSTALLATION
INSTALLATION - CENTER BEZEL OUTLETS
(1) Position the center bezel outlets and housing
onto the center bezel as a unit.
Fig. 3 Center Air Outlets
1 - CENTER BEZEL
2 - CENTER BEZEL OUTLETS
3 - SCREW (3)
4 - INSTRUMENT PANEL SWITCH BANK
5 - CONNECTOR (ATC ONLY)
6 - JUMPER HARHESS (ATC ONLY)
Fig. 4 Demister Outlet
1 - DEMISTER OUTLET
2 - INSTRUMENT PANEL TOP PAD
3 - TRIM STICK
RSDISTRIBUTION - FRONT24-45
AIR OUTLETS (Continued)

blower motor to regulate the blower motor ground
path it provides. The blower motor and wheel are
used to control the velocity of air moving through the
HVAC housing by spinning the blower wheel within
the housing at the selected speed or, in the ATC sys-
tem, at the selected or programmed speed.
DIAGNOSIS AND TESTING - BLOWER MOTOR
BLOWER MOTOR INOPERATIVE
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.
For circuit descriptions and diagrams, refer to the
appropriate wiring information. The wiring informa-
tion includes wiring, diagrams, proper wire and con-
nector repair procedures, further details on wire
harness routing and retention, as well as pin-out and
location views for the various wire harness connec-
tors, splices and grounds.
BLOWER MOTOR ELECTRICAL DIAGNOSIS
(1) Check the fuse (Fuse 10 - 40 ampere) in the
Integrated Power Module (IPM). 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 On position. Be
certain that the A/C-heater control power is turned
on. Check for battery voltage at the fuse (Fuse 10 -
40 ampere) in the IPM. If OK, go to Step 3. If not
OK, check the front blower motor relay.
(3) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the front HVAC wire harness connector
for the front blower motor resistor block (Manual
Temperature Control) or the front blower motor
power module (Automatic Temperature Control) from
the resistor or module connector receptacle. Recon-
nect the battery negative cable. Turn the ignition
switch to the On position. Be certain that the A/C-
heater control power is turned on. Check for battery
voltage at the fused front blower motor relay output
circuit cavity of the front HVAC wire harness connec-
tor for the front blower motor resistor block (MTC) orthe front blower motor power module (ATC). If OK,
go to Step 4. If not OK, repair the open fused front
blower motor relay output circuit to the IPM as
required.
(4) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the front blower motor pigtail wire con-
nector from the connector receptacle of the front
blower motor resistor block (MTC) or the front
blower motor power module (ATC). Use jumper wires
to connect a battery and ground feeds to the blower
motor pigtail wire connector. The blower motor
should operate. If OK with MTC, proceed to diagno-
sis of the front blower motor resistor block (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/BLOWER MOTOR RESISTOR - DIAGNO-
SIS AND TESTING). If OK with ATC, use a DRBIII
scan tool to diagnose the front blower motor power
module. Refer to Body Diagnostic information. If not
OK with MTC or ATC, replace the faulty front blower
motor.
BLOWER MOTOR NOISE OR VIBRATION
Refer to the Blower Motor Noise/Vibration Diagno-
sis chart for basic checks of the blower motor when a
vibration or noise is present (Fig. 7).
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.
NOTE: The blower motor is located on the passen-
ger side of the vehicle under the instrument panel.
The blower motor can be removed from the vehicle
without having to remove the HVAC housing.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the passenger side door sill plate and
cowl panel.
(3) Pull back the carpet to access the front lower
air intake screw.
RSDISTRIBUTION - FRONT24-47
BLOWER MOTOR (Continued)

(6) Install the four screws (from the bottom) that
secure the lower air inlet housing to the lower HVAC
housing. Tighten the screws to 2 N´m (17 in. lbs.).
(7) Install the one screw (from the top) that
secures the lower air inlet housing to the upper air
intake housing. Tighten the screws to 2 N´m (17 in.
lbs.).
(8) Connect the blower motor pigtail harness con-
nector to the blower motor resistor block or power
module, depending how vehicle is equipped.
(9) Install the recirculation door actuator (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS/
RECIRCULATION DOOR ACTUATOR - INSTALLA-
TION).
(10) Install the recirculation door actuator wire
harness lead into the routing clip on the lower air
inlet housing.
(11) Reinstall the carpet.
(12) Install the passenger side door sill plate and
cowl panel.
(13) Reconnect the battery negative cable.
(14) Perform the heater-A/C control calibration
procedure (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - FRONT/A/C-HEATER CON-
TROL - STANDARD PROCEDURE - HEATER-A/C
CONTROL CALIBRATION).
DEFROSTER DUCT
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 instrument panel from the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).
(3) Place the instrument panel face down on a
suitable work surface. Be certain to take the proper
precautions to protect the face of the instrument
panel from cosmetic damage.(4) Remove the fasteners that secure the defroster
duct to the instrument panel armature.
(5) Remove the defroster duct 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. 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 defroster duct to the instrument
panel.
(2) Install the fasteners that secure the defroster
duct to the instrument panel armature.
(3) Reinstall the instrument panel in the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(4) Reconnect the battery negative cable.
FLOOR DISTRIBUTION DUCTS
REMOVAL
(1) Roll back the carpet on the front floor from
under the instrument panel toward the rear of the
vehicle (Refer to 23 - BODY/INTERIOR/CARPETS
AND FLOOR MATS - REMOVAL).
(2) Lift the center floor distribution duct upward
far enough to disengage its locator hole from the
weld stud on the front floor panel (Fig. 11).
(3) Pull the center floor distribution duct rearward
far enough to disengage it from the floor outlet of the
HVAC housing.
(4) Disassemble the right and/or left floor distribu-
tion ducts from the center floor distribution duct as
required.
INSTALLATION
(1) Assemble the right and/or left floor distribution
ducts onto the center floor distribution duct as
required.
(2) Slide the center floor distribution duct under
the instrument panel center stack far enough to
engage it to the floor outlet of the HVAC housing.
24 - 50 DISTRIBUTION - FRONTRS
BLOWER MOTOR (Continued)

(3) Align the locator hole on the center floor distri-
bution duct with the weld stud on the front floor
panel.
(4) Using hand pressure, push the locator hole of
the center floor distribution duct down over the weld
stud on the front floor panel.
(5) Reinstall the carpet onto the front floor panel
and under the instrument panel (Refer to 23 - BODY/
INTERIOR/CARPETS AND FLOOR MATS -
INSTALLATION).
HVAC HOUSING
REMOVAL
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) AND (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
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) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(3) Disconnect and isolate the negative battery
cable.
(4) Remove the windshield wiper module from the
vehicle (Refer to 8 - ELECTRICAL/WIPERS/WASH-
ERS/WIPER MODULE - REMOVAL).
(5) Disconnect the liquid line and suction line from
the expansion valve (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - FRONT/LIQUID
LINE - REMOVAL) and (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - FRONT/SUC-
TION LINE - REMOVAL).
(6) Disconnect the heater hoses from the heater
core tubes (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - FRONT/HEATER HOSE -
REMOVAL).
(7) On LHD models, remove the one bolt that
secures the HVAC housing to the dash panel (Fig.
12).
(8) Remove the three nuts that secure the HVAC
housing to the dash panel.
(9) Remove the instrument panel from the passen-
ger compartment (Refer to 23 - BODY/INSTRU-
MENT PANEL/INSTRUMENT PANEL ASSEMBLY -
REMOVAL).
(10) Remove the floor distribution duct (Refer to
24 - HEATING & AIR CONDITIONING/DISTRIBU-
TION - FRONT/FLOOR DISTRIBUTION DUCTS -
REMOVAL).
(11) Remove the bolt or bolts (depending on appli-
cation) that secure the HVAC housing to the passen-
ger compartment side of the dash panel (Fig. 13) or
(Fig. 14).
(12) Pull the HVAC housing rearward far enough
for the mounting studs to clear the dash panel and
remove the housing from the passenger compart-
ment.
DISSASEMBLY
(1) Remove the HVAC housing from the vehicle
and place it on a workbench (Refer to 24 - HEATING
& AIR CONDITIONING/DISTRIBUTION - FRONT/
HVAC HOUSING - REMOVAL).
Fig. 11 Floor Distribution Ducts - LHD Shown, RHD
Typical
1 - CENTER FLOOR DISTRIBUTION DUCT
2 - RIGHT FLOOR DISTRIBUTION DUCT
3 - LEFT FLOOR DISTRIBUTION DUCT
4 - WELD STUD
RSDISTRIBUTION - FRONT24-51
FLOOR DISTRIBUTION DUCTS (Continued)

INSTRUMENT PANEL
DEMISTER DUCTS
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 instrument panel from the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).
(3) Place the instrument panel face down on a
suitable work surface. Be certain to take the proper
precautions to protect the face of the instrument
panel from cosmetic damage.
(4) Remove the fasteners that secure the demister
ducts to the instrument panel armature.
(5) Disengage the demister ducts from the demis-
ter outlets.
(6) Remove the demister ducts from the instru-
ment 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. 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 demister ducts to the instrument
panel.(2) Engage the demister ducts to the demister out-
lets.
(3) Install the fasteners that secure the demister
ducts to the instrument panel armature.
(4) Reinstall the instrument panel into the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(5) Reconnect the battery negative cable.
INSTRUMENT PANEL DUCTS
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 instrument panel from the vehicle
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).
(3) Place the instrument panel face down on a
suitable work surface. Be certain to take the proper
precautions to protect the face of the instrument
panel from cosmetic damage.
(4) Remove the screws that secure the panel ducts
to the instrument panel armature.
(5) Disengage the panel ducts from the panel out-
lets.
(6) Remove the panel ducts from the instrument
panel.
INSTALLATION
(1) Position the panel ducts to the instrument
panel.
(2) Engage the panel ducts to the panel outlets.
(3) Install the screws that secure the panel ducts
to the instrument panel armature.
(4) Reinstall the instrument panel into the vehicle
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(5) Reconnect the battery negative cable.
RSDISTRIBUTION - FRONT24-55

INSTALLATION
(1) Position the discharge line into the engine com-
partment.
(2) Remove the tape or plugs from the compressor
discharge port and the discharge line fitting.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the discharge line fit-
ting.
(4) Install a new dual plane seal and reconnect the
discharge line fitting to the compressor discharge
port on the top of the compressor.
(5) Install the nut that secures the discharge line
fitting to the compressor. Tighten the nut to 23 N´m
(17 ft. lbs.).
(6) Remove the tape or plugs from the condenser
inlet port and the discharge line fitting.
(7) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the discharge line fit-
ting.
(8) Install a new dual plane seal and reconnect the
discharge line fitting to the condenser inlet port on
the right side of the cooling module.
(9) Install the nut that secures the discharge line
fitting to the condenser. Tighten the nut to 23 N´m
(17 ft. lbs.).
(10) Position the radiator sight shield onto the
radiator closure panel crossmember.
(11) Install the five small screws that secure the
front fascia grille inserts to the radiator sight shield.
Tighten the screws to 2 N´m (17 in. lbs.).
(12) Install and tighten the two large screws that
secure the front fascia and the outboard ends of the
radiator sight shield to the radiator closure panel
crossmember. Tighten the screws to 6 N´m (53 in.
lbs.).
(13) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(14) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
A/C EVAPORATOR
DESCRIPTION
The A/C evaporator is located in the HVAC hous-
ing, behind the instrument panel. The evaporator is
positioned in the housing so that all air that enters
the housing must pass over the fins of the evaporator
coils before it is distributed through the system ducts
and outlets. However, air passing over the evaporator
fins will only be conditioned when the compressor isengaged and circulating refrigerant through the
evaporator tubes.
OPERATION
Refrigerant enters the A/C evaporator from the
expansion valve as a low-temperature, low-pressure
liquid. As air flows over the fins of the evaporator,
the humidity in the air condenses on the fins, and
the heat from the air is absorbed by the refrigerant.
Heat absorption causes the refrigerant to boil and
vaporize. The refrigerant becomes a low-pressure gas
when it leaves the evaporator.
The A/C evaporator cannot be repaired and, if
faulty or damaged, it must be replaced.
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) Remove the HVAC housing (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - REMOVAL).
(2) Disassemble the HVAC housing to access the
evaporator (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION/HVAC HOUSING - DIS-
ASSEMBLY).
(3) Carefully lift the evaporator and its foam wrap
out of the lower half of the HVAC housing as a unit.
Be certain not to lose the clam shell type rubber seal
that is fitted to the evaporator inlet and outlet tubes
where they exit the HVAC housing.
INSTALLATION
NOTE: If the evaporator is being replaced, add 50
milliliters (1.8 fluid ounces) of refrigerant oil to the
refrigerant system. Use only refrigerant oil of the
type recommended for the compressor in the vehi-
cle.
(1) Carefully lower the evaporator and its foam
wrap into the lower half of the HVAC housing as a
unit. Be certain that the clam shell type rubber seal
24 - 80 PLUMBING - FRONTRS
A/C DISCHARGE LINE (Continued)

(8) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the front liquid
line rear section and suction line fittings for the
expansion valve.
(9) Connect the liquid line and suction line fittings
to the expansion valve.
(10) Install the nut that secures the suction line
and liquid line fittings to the stud on the expansion
valve. Tighten the nut to 23 N´m (17 ft. lbs.).
(11) Remove the tape or plugs from the liquid line
rear section fitting and the receiver/drier outlet port.
(12) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(13) Connect the liquid line fitting to the receiver/
drier outlet port.
(14) Install the screw that secures the liquid line
fitting to the receiver/drier. Tighten the screw to 11
N´m (97 in. lbs.).
(15) Connect the wire harness connector to the A/C
pressure transducer.
(16) Connect the drain tube to the wiper module
drain on the right side of the engine compartment.
(17) Install the air cleaner housing.
(18) Reconnect the battery negative cable.
(19) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(20) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
HEATER CORE
DESCRIPTION
The heater core is located in the distribution hous-
ing, which is attached to the HVAC housing, behind
the instrument panel. It is a heat exchanger made of
rows of tubes and fins. One end of the core is fitted
with a molded plastic tank, which includes integral
heater core inlet and outlet ports. Removable heater
core tubes attach to the ports by use of a sealing
plate secured with a screw to the heater core tank.
This removable heater core tube arrangement allows
the heater core to be serviced without removing the
HVAC housing from the vehicle.
OPERATION
Engine coolant is circulated through heater hoses
to the heater core at all times. As the coolant flows
through the heater core, heat removed from the
engine is transferred to the heater core fins and
tubes. Air directed through the heater core picks up
the heat from the heater core fins. The blend doorallows control of the heater output air temperature
by regulating the amount of air that is flowing
through the heater core within the HVAC housing.
The heater core cannot be repaired and, if faulty or
damaged, it must be replaced.
REMOVAL
REMOVAL - HEATER CORE TUBES
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) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Disconnect and isolate the battery negative
cable.
(3) Disconnect the heater hoses from the heater
core tubes (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/HEATER INLET HOSE -
REMOVAL) and (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING/HEATER RETURN
HOSE - REMOVAL).
(4) Remove the silencer from beneath the driver
side end of the instrument panel.
NOTE: Take the proper precautions to protect the
carpeting below the heater core from spilled engine
coolant and have absorbent toweling readily avail-
able to clean up any spills.
(5) Remove the screw that secures the heater core
tube sealing plate to the heater core supply and
return ports (Fig. 14).
(6) Push both heater core tubes simultaneously
toward the dash panel far enough to disengage their
fittings from the heater core supply and return ports.
(7) Install plugs in, or tape over the opened heater
core tube fittings and both heater core ports.
(8) Pull both heater core tubes simultaneously
slightly away from the distribution housing and rear-
ward far enough to disengage the engine compart-
ment ends of the tubes from the dash panel seal.
RSPLUMBING - FRONT24-83
EXPANSION VALVE (Continued)

(9) Remove the heater core tubes and sealing plate
as a unit from beneath the instrument panel.
(10) Use absorbent toweling to clean up any
engine coolant spills from the preceding operation.
REMOVAL - HEATER CORE
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) Remove the silencer boot fasteners located
around the base of the lower steering shaft from the
dash panel so that it may be pushed aside.
(2) Remove the brake lamp switch from its mount-
ing bracket (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR/BRAKE LAMP SWITCH -
REMOVAL).
(3) Disconnect the power brake booster input rod
(push rod) from the pin on the brake pedal arm
(Refer to 5 - BRAKES - ABS/HYDRAULIC/ME-CHANICAL/POWER BRAKE BOOSTER -
REMOVAL).
(4) Remove the heater core tubes (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/
HEATER CORE - REMOVAL).
(5) Remove the two screws that secure the heater
core mounting plate to the distribution housing.
(6) While pulling the accelerator pedal upward
(Fig. 15) and pushing the brake pedal downward
(Fig. 16) far enough for clearance, pull the heater
core out of the distribution housing.
(7) Use absorbent toweling to mop up any engine
coolant spills from the preceding operation. Also, if
the heater core was leaking, use absorbent toweling
and reach into the heater core opening to mop up
any residual engine coolant within the distribution
housing.
Fig. 14 Heater Core Tubes - LHD Shown, RHD
Typical
1 - SEAL
2 - HEATER CORE TUBES
3 - SCREW
4 - HEATER CORE
5 - DISTRIBUTION HOUSING
6 - SEALING PLATE
Fig. 15 Accelerator Pedal - LHD Shown, RHD Typical
1 - HEATER CORE
Fig. 16 Brake Pedal - LHD Shown, RHD Typical
1 - HEATER CORE
2 - BRAKE PEDAL
24 - 84 PLUMBING - FRONTRS
HEATER CORE (Continued)

INSTALLATION
INSTALLATION - HEATER CORE TUBES
(1) Remove the plugs or tape from both heater core
tube fittings and both heater core ports.
(2) Position the heater core tubes and sealing plate
as a unit beneath the instrument panel.
(3) Align the engine compartment ends of both
heater core tubes with the openings in the dash
panel seal and push them simultaneously forward
through the seal far enough to engage the heater
core ends of the tubes with the heater core supply
and return ports.
(4) Position both heater core tubes and the sealing
plate simultaneously to the heater core supply and
return ports.
NOTE: The heater core tubes each have a slot that
must be indexed to a location tab within each of the
heater core ports. Adjust the position of the tubes
as required so that the sealing plate fits flush
against the heater core supply and return ports,
which indicates that the tubes are properly indexed.
(5) Index both heater core tubes to the heater core
ports.
(6) Install the screw that secures the heater core
tube sealing plate to the heater core supply and
return ports. Tighten the screw to 3 N´m (27 in. lbs.).
(7) Install the silencer under the driver side end of
the instrument panel.
(8) Connect the heater hoses to the heater hose
tubes (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING/HEATER INLET HOSE - INSTAL-
LATION) and(Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING/HEATER RETURN
HOSE - INSTALLATION).
(9) Reconnect the battery negative cable.
(10) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
INSTALLATION - HEATER CORE
(1) While pushing the brake pedal downward and
pulling the accelerator pedal upward far enough for
clearance, slide the heater core into the distribution
housing.
(2) Install the two screws that secure the heater
core mounting plate to the distribution housing.
Tighten the screws to 2 N´m (17 in. lbs.).
(3) Install the heater core tubes (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/
HEATER CORE - INSTALLATION).
(4) Reconnect the power brake booster input rod
(push rod) to the pin on the brake pedal arm (Referto 5 - BRAKES/HYDRAULIC/MECHANICAL/
POWER BRAKE BOOSTER - INSTALLATION).
(5) Reinstall the brake lamp switch into its mount-
ing bracket (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR/BRAKE LAMP SWITCH -
INSTALLATION).
(6) Reinstall the silencer boot around the base of
the lower steering shaft on the dash panel.
(7) Reconnect the battery negative cable.
(8) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
(9) Operate system for two thermostat cycles to
assure the elimination of any air that may be
trapped within the cooling system.
HEATER INLET HOSE
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING).
NOTE: The heater inlet hose is constructed from
formed steel tubing and rubber hoses. Depending
on application, the ends are secured to the heater
core, engine oil cooler or the engine by spring ten-
sion clamps.
(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Using spring tension clamp pliers, compress
and slide the clamps off of each end of the hose being
removed (Fig. 17), (Fig. 18) or (Fig. 19).
CAUTION:
DO NOT apply excessive pressure on heater tubes
or connections when removing heater hoses.
Excessive pressure may damage or deform the
tubes/heater core, causing an engine coolant leak.
(3) Disconnect each hose end by carefully twisting
the hose back and forth on the tube or nipple, while
gently pulling it away from the end of the tube or
nipple.
NOTE:
Replacement of the heater inlet hoses will be
required if the hose ends are cut for removal.
(4) If necessary, carefully cut the hose end and
peel the hose off of the tube or nipple.
RSPLUMBING - FRONT24-85
HEATER CORE (Continued)

The following is a list of the monitored compo-
nents:
²Comprehensive Components
²Oxygen Sensor Monitor
²Oxygen Sensor Heater Monitor
²Catalyst Monitor
COMPREHENSIVE COMPONENTS
Along with the major monitors, OBD II requires
that the diagnostic system monitor any component
that could affect emissions levels. In many cases,
these components were being tested under OBD I.
The OBD I requirements focused mainly on testing
emissions-related components for electrical opens and
shorts.
However, OBD II also requires that inputs from
powertrain components to the PCM be tested for
rationality, and that outputs to powertrain compo-
nents from the PCM be tested forfunctionality.
Methods for monitoring the various Comprehensive
Component monitoring include:
(1) Circuit Continuity
²Open
²Shorted high
²Shorted to ground
(2) Rationality or Proper Functioning
²Inputs tested for rationality
²Outputs tested for functionality
NOTE: Comprehensive component monitors are
continuous. Therefore, enabling conditions do not
apply.
Input RationalityÐWhile input signals to the
PCM are constantly being monitored for electrical
opens and shorts, they are also tested for rationality.
This means that the input signal is compared against
other inputs and information to see if it makes sense
under the current conditions.
PCM sensor inputs that are checked for rationality
include:
²Manifold Absolute Pressure (MAP) Sensor
²Oxygen Sensor (O2S)
²Engine Coolant Temperature (ECT) Sensor
²Camshaft Position (CMP) Sensor
²Vehicle Speed Sensor
²Crankshaft Position (CKP) Sensor
²Intake/inlet Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Ambient Temperature Sensors
²Power Steering Switch
²Oxygen Sensor Heater
²Brake Switch
²Leak Detection Pump Switch or NVLD switch (if
equipped)
²P/N SwitchOutput FunctionalityÐPCM outputs are tested
for functionality in addition to testing for opens and
shorts. When the PCM provides a voltage to an out-
put component, it can verify that the command was
carried out by monitoring specific input signals for
expected changes. For example, when the PCM com-
mands the Idle Air Control (IAC) Motor to a specific
position under certain operating conditions, it expects
to see a specific (target) idle speed (RPM). If it does
not, it stores a DTC.
PCM outputs monitored for functionality include:
²Fuel Injectors
²Ignition Coils
²Idle Air Control
²Purge Solenoid
²EGR Solenoid (if equipped)
²LDP Solenoid or NVLD solenoid (if equipped)
²Radiator Fan Control
²Trans Controls
OXYGEN SENSOR (O2S) MONITOR
DESCRIPTIONÐEffective control of exhaust
emissions is achieved by an oxygen feedback system.
The most important element of the feedback system
is the O2S. The O2S is located in the exhaust path.
Once it reaches operating temperature 300É to 350ÉC
(572É to 662ÉF), the sensor generates a voltage that
is inversely proportional to the amount of oxygen in
the exhaust. When there is a large amount of oxygen
in the exhaust caused by a lean condition, the sensor
produces a low voltage, below 450 mV. When the oxy-
gen content is lower, caused by a rich condition, the
sensor produces a higher voltage, above 450mV (volt-
ages are offset by 2.5 volts on NGC vehicles).
The information obtained by the sensor is used to
calculate the fuel injector pulse width. The PCM is
programmed to maintain the optimum air/fuel ratio.
At this mixture ratio, the catalyst works best to
remove hydrocarbons (HC), carbon monoxide (CO)
and nitrous oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the
EGR (if equipped), Catalyst and Fuel Monitors.
The O2S may fail in any or all of the following
manners:
²Slow response rate (Big Slope)
²Reduced output voltage (Half Cycle)
²Heater Performance
Slow Response Rate (Big Slope)ÐResponse rate
is the time required for the sensor to switch from
lean to rich signal output once it is exposed to a
richer than optimum A/F mixture or vice versa. As
the PCM adjusts the air/fuel ratio, the sensor must
be able to rapidly detect the change. As the sensor
ages, it could take longer to detect the changes in the
oxygen content of the exhaust gas. The rate of
change that an oxygen sensor experiences is called
25 - 2 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)