2004 CHRYSLER VOYAGER Temperature

(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)

(21) Install a new tie strap just forward of the con-
nections between the underbody plumbing and the
engine compartment plumbing for the rear heater
and air conditioner.
(22) Lower the vehicle.
(23) Reconnect the negative battery cable.
(24) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(25) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
RECEIVER / DRIER
DESCRIPTION
The receiver/drier is mounted in a bracket secured
to the right front strut tower in the engine compart-
ment. The receiver/drier is connected between the
front and rear sections of the liquid line between the
condenser outlet and the evaporator inlet. The receiv-
er/drier cannot be repaired. If the receiver/drier is
faulty or damaged, or if the refrigerant system has
been contaminated or left open to the atmosphere for
an indeterminable period or if the A/C compressor
has failed, it must be replaced.
OPERATION
The receiver/drier performs a filtering action to
prevent foreign material in the refrigerant from con-
taminating the expansion valve. Desiccant inside the
receiver/drier canister absorbs any moisture which
may have entered and become trapped within the
refrigerant system. In addition, during periods of
high demand air conditioner operation, the receiver/
drier acts as a reservoir to store surplus refrigerant.
Refrigerant enters the receiver/drier as a high-pres-
sure, low temperature liquid.
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 -
FRONT - WARNING - A/C PLUMBING) and (Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - CAUTION - A/C PLUMBING).
(1) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).(2) Remove the air cleaner housing from the right
side of the engine compartment.
(3) Remove the bolt that secures the liquid line
front section fitting to the top of the receiver/drier
(Fig. 27).
(4) Disconnect the liquid line fitting from the
receiver/drier inlet port.
(5) Remove the O-ring seal from the liquid line fit-
ting and discard.
(6) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier inlet port.
(7) Remove the bolt that secures the liquid line
rear section fitting to the top of the receiver/drier.
(8) Disconnect the liquid line fitting from the
receiver/drier outlet port.
(9) Remove the seal from the liquid line fitting and
discard.
(10) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier outlet port.
(11) Remove the two nuts that secure the receiver/
drier mounting bracket to the weld studs on the side
of the right front strut tower.
Fig. 27 Reciever/Drier - LHD Shown, RHD Typical
1 - A/C GROUND STRAP (IF EQUIPPED)
2 - NUT (IF EQUIPPED)
3 - WELD STUD (IF EQUIPPED)
4 - A/C PRESSURE TRANSDUCER
5 - WELD STUD (2)
6 - EXPANSION VALVE
7 - FRONT LIQUID LINE REAR SECTION
8 - LIQUID LINE EXTENSION (REAR A/C ONLY)
9 - NUT (2)
10 - RECEIVER/DRIER
11 - ROUTING CLIP
12 - FRONT LIQUID LINE FRONT SECTION
RSPLUMBING - FRONT24-91
LIQUID LINE (Continued)

STANDARD PROCEDURE - REFRIGERANT OIL
LEVEL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - WARNING - A/C PLUMBING) and (Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - CAUTION - A/C PLUMBING).
CAUTION: Use only PAG oils that are designed to
work with R-134a refrigerant and the A/C compres-
sor in the vehicle. Refer to the underhood A/C Sys-
tem Specification Label.
It is important to have the correct amount of lubri-
cant in the A/C refrigerant system to ensure proper
lubrication of the A/C compressor. Too little lubricant
will result in damage to the compressor. Too much
lubricant will reduce the cooling capacity of the A/C
system and consequently result in higher discharge
air temperatures.
The lubricant used in the compressor is polyalka-
lene glycol PAG lubricant. Only the refrigerant lubri-
cant approved for use with this vehicle should be
used to service the system. Do not use any other
lubricant. The lubricant container should be kept
tightly capped until it is ready for use. Refrigerant
lubricant will quickly absorb any moisture it comes
in contact with.
It will not be necessary to check the oil level in the
A/C compressor or to add oil, unless there has been
an oil loss. An oil loss may occur due to a rupture or
leak from a refrigerant line, connector fitting, compo-
nent or component seal. If a leak occurs, add 30 mil-
liliters (1 fluid ounce) of the recommended
refrigerant oil to the refrigerant system after the
repair has been made. Refrigerant oil loss will be evi-
dent at the leak point by the presence of a wet, shiny
surface around the leak.
REFRIGERANT OIL LEVEL CHECK
When an air conditioning system is first assembled
at the factory, all components (except the A/C com-
pressor) are refrigerant oil free. After the refrigerant
system has been charged with (R-134a) refrigerant
and operated, the oil in the A/C compressor is dis-
persed through the lines and components. The A/C
evaporator, A/C condenser, and receiver/drier will
retain a significant amount of oil. Refer to the A/C
Component Refrigerant Oil Capacities table. When a
component is replaced, the specified amount of refrig-
erant oil must be added. When the compressor is
replaced, the amount of oil that is retained in the
rest of the system must be drained from the replace-ment A/C compressor. The oil capacity of the system,
minus the amount of oil still in the remaining com-
ponents (refer to the oil capacity chart below) can be
measured and poured into the suction port of the A/C
compressor. When a line or component has ruptured
and oil has escaped, the receiver/drier must be
replaced along with the ruptured component.
Example: On an A/C system the A/C evaporator
retains 60 ml. (2 oz.). The A/C condenser retains 30
ml. (1 oz.) of oil, and system capacity may be 150 ml.
(5.00 oz.) of oil.
150 ml. minus 90 ml. equals 60 ml. (2.00 oz.).
A/C COMPONENT REFRIGERANT OIL
CAPACITIES
Front A/C Front & Rear
A/C
COMPONENT ml fl oz ml fl oz
Total System Fill 180 6.1 300 10.14
Receiver/Drier 25 0.9 25 0.9
A/C Condenser 50 1.8 50 1.8
Front Evaporator 50 1.8 50 1.8
Rear Evap. (including
underbody lines)N/A N/A 50 1.8
A/C Compressor Drain and measure the oil
from the old compressor -
See text above.
VERIFY REFRIGERANT LUBRICANT LEVEL
(1) Recover the refrigerant from the system.
(2) Disconnect the refrigerant lines from the A/C
compressor. Cap open lines to prevent moisture from
entering the system.
(3) Remove A/C compressor from the vehicle.
(4) From the suction and discharge ports on the
A/C compressor, drain the lubricant from the com-
pressor.
(5) Add the system capacity minus the capacity of
the components that have not been replaced. Refer to
the A/C Component Refrigerant Oil Capacities chart.
Add lubricant through the suction and discharge
ports on the A/C compressor.
(6) Install the A/C compressor and connect the
refrigerant lines. Then evacuate and charge refriger-
ant system.
(7) Most reclaim/recycling equipment will measure
the lubricant being removed. This amount of lubri-
cant should be added back to the system. If a new
A/C compressor is being installed, drain the lubricant
from the used compressor, measure the amount
drained and discard the used lubricant. Drain the
lubricant from the new A/C compressor into a clean
container. Return the amount of lubricant measured
from the used compressor, plus the amount reclaimed
RSPLUMBING - FRONT24-93
REFRIGERANT OIL (Continued)

PLUMBING - REAR
TABLE OF CONTENTS
page page
A/C EVAPORATOR
DESCRIPTION.........................97
OPERATION...........................97
REMOVAL
REMOVAL - REAR A/C EVAPORATOR......97
REMOVAL - A/C EVAPORATOR LINE
EXTENSION.........................98
INSTALLATION
INSTALLATION - REAR A/C EVAPORATOR . . 99
INSTALLATION - REAR A/C EVAPORATOR
LINE EXTENSION.....................99
A/C EXPANSION VALVE
DESCRIPTION.........................99
OPERATION...........................99
DIAGNOSIS AND TESTING - EXPANSION
VALVE .............................100
REMOVAL............................100
INSTALLATION........................100
HEATER CORE
DESCRIPTION........................101
OPERATION..........................101
STANDARD PROCEDURE - REAR HEATER
CORE FILLING......................101REMOVAL............................102
INSTALLATION........................103
HEATER HOSES
REMOVAL............................103
INSTALLATION........................104
LIQUID LINE
REMOVAL............................104
INSTALLATION........................105
SUCTION LINE
REMOVAL............................106
INSTALLATION........................107
UNDERBODY LINES
DESCRIPTION........................107
OPERATION..........................107
REMOVAL
REMOVAL - UNDERBODY HEATER TUBES . 109
REMOVAL - UNDERBODY REFRIGERANT
LINES.............................110
INSTALLATION
INSTALLATION - REAR HEATER LINES....111
INSTALLATION - UNDERBODY
REFRIGERANT LINES.................111
A/C EVAPORATOR
DESCRIPTION
The rear A/C evaporator is located in the rear
HVAC housing, behind the right rear wheel house.
The evaporator is positioned in the rear 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 condi-
tioned when the compressor is engaged and circulat-
ing refrigerant through the evaporator tubes. The
rear HVAC housing must be removed from the vehi-
cle to access the A/C evaporator for service.
OPERATION
Refrigerant enters the rear evaporator from the
rear expansion valve as a low-temperature, low-pres-
sure liquid. As air flows over the fins of the evapora-
tor, the humidity in the air condenses on the fins,
and the heat from the air is absorbed by the refrig-
erant. Heat absorption causes the refrigerant to boil
and vaporize. The refrigerant becomes a low-pressure
gas when it leaves the evaporator.
REMOVAL
REMOVAL - REAR A/C EVAPORATOR
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - WARNING - A/C PLUMBING), (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT - CAUTION - A/C PLUMBING), and (Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - WARNING - HEATER PLUMBING).
(1) Remove the rear HVAC housing from the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL).
(2) Remove the rear evaporator line extension from
the expansion valve (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EVAPORA-
TOR - REMOVAL - EVAPORATOR LINE EXTEN-
SION).
(3) Remove the rear expansion valve from the rear
evaporator (Refer to 24 - HEATING & AIR CONDI-
RSPLUMBING - REAR24-97

(8) Remove the nut that secures the evaporator
line extension seal plate to the expansion valve stud.
(9) Remove the evaporator line extension seal
plate from the expansion valve stud.
(10) Remove the evaporator line extension from
the expansion valve and the rear HVAC housing
base.
(11) Remove the seals from the evaporator line
extension fittings and discard.
(12) Install plugs in, or tape over the opened evap-
orator line extension fittings and both expansion
valve ports.
INSTALLATION
INSTALLATION - REAR A/C EVAPORATOR
NOTE: If the rear A/C 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
vehicle.
(1) Carefully lower the rear A/C evaporator and its
foam wrap into the lower half of the rear HVAC
housing.
(2) Position the upper half of the rear HVAC hous-
ing onto the lower half.
(3) Install the three metal spring clips that secure
the upper half of the rear HVAC housing to the lower
half.
(4) Install the three screws that secure the upper
half of the rear HVAC housing to the lower half.
Tighten the screws to 2 N´m (17 in. lbs.).
(5) Install the rubber grommet that seals the evap-
orator inlet and outlet tubes to the rear HVAC hous-
ing near the expansion valve.
(6) Reinstall the rear expansion valve onto the
rear A/C evaporator (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EXPANSION
VALVE - INSTALLATION).
(7) Reinstall the rear evaporator extension line
onto the expansion valve (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - REAR/EVAPO-
RATOR - INSTALLATION - EVAPORATOR EXTEN-
SION LINE).
(8) Reinstall the rear HVAC housing into the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION - REAR/REAR HEATER-A/C
HOUSING - INSTALLATION).
INSTALLATION - REAR A/C EVAPORATOR LINE
EXTENSION
(1) Remove the tape or plugs from the evaporator
line extension fittings and both expansion valve
ports.(2) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the evaporator
line extension fittings.
(3) Position the evaporator line extension to the
expansion valve and the rear HVAC housing base.
(4) Position the evaporator line extension seal
plate over the expansion valve stud.
(5) Install the nut that secures the evaporator line
extension seal plate to the expansion valve stud.
Tighten the nut to 23 N´m (17 ft. lbs.).
(6) Position the expansion valve bracket over the
expansion valve stud.
(7) Install the two screws that secure the expan-
sion valve bracket to the lower rear HVAC housing.
Tighten the screws to 2 N´m (17 in. lbs.).
(8) Install the nut that secures the expansion
valve bracket to the expansion valve stud. Tighten
the nut to 23 N´m (17 ft. lbs.).
(9) Carefully restore the expansion valve foam
insulator wrap back around the expansion valve.
(10) Position the plate that captures and seals the
evaporator line extension onto the rear HVAC hous-
ing base.
(11) Install the screw that secures the capture
plate to the base of the rear HVAC housing. Tighten
the screw to 2 N´m (17 in. lbs.).
(12) Install the rear HVAC housing into the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING -
INSTALLATION).
A/C EXPANSION VALVE
DESCRIPTION
The rear ªHº valve-type thermal expansion valve
(TXV) is located at the rear of the rear HVAC hous-
ing between the evaporator line extension and the
evaporator coil. High-pressure, low temperature liq-
uid refrigerant from the liquid line passes through
the expansion valve orifice, converting it into a low-
pressure, low-temperature mixture of liquid and gas
before it enters the evaporator coil.
OPERATION
A mechanical sensor in the expansion valve control
head monitors the temperature and pressure of the
refrigerant leaving the evaporator coil through the
suction line, and adjusts the orifice size at the liquid
line to let the proper amount of refrigerant into the
evaporator coil to meet the vehicle cooling require-
ments. Controlling the refrigerant flow through the
evaporator ensures that none of the refrigerant leav-
ing the evaporator is still in a liquid state, which
could damage the compressor.
RSPLUMBING - REAR24-99
A/C EVAPORATOR (Continued)

The rear A/C expansion valve cannot be adjusted
or repaired and, if faulty or damaged, it must be
replaced.
DIAGNOSIS AND TESTING - EXPANSION VALVE
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
NOTE: The expansion valve should only be tested
following testing of the compressor.
NOTE: Liquid CO
2is required to test the expansion
valve. This material is available from most welding
supply facilities. Liquid CO
2is also available from
companies which service and sell fire extinguish-
ers.
When testing the expansion valve, the work area
and the vehicle temperature must be 21É to 27É C
(70É to 85É F). To test the expansion valve:
(1) Connect a charging station or manifold gauge
set to the refrigerant system service ports. Verify the
refrigerant charge level.
(2) Close all doors, windows and vents to the pas-
senger compartment.
(3) Set the heater-air conditioner controls so that
the compressor is operating, the temperature control
is in the highest temperature position, the mode door
is directing the output to the floor outlets, and the
blower is operating at the highest speed setting.
(4) Start the engine and allow it to idle at 1000
rpm. After the engine has reached normal operating
temperature, allow the passenger compartment to
heat up. This will create the need for maximum
refrigerant flow into the evaporator.
(5) If the refrigerant charge is sufficient, the dis-
charge (high pressure) gauge should read 965 to 1655
kPa (140 to 240 psi). The suction (low pressure)
gauge should read 140 kPa to 207 kPa (20 psi to 30
psi). If OK, go to Step 6. If not OK, replace the faulty
expansion valve.
WARNING: PROTECT THE SKIN AND EYES FROM
EXPOSURE TO LIQUID CO
2. PERSONAL INJURY
CAN RESULT.
(6) If the suction (low pressure) gauge reads
within the specified range, freeze the expansion valve
control head for 30 seconds using liquid CO
2or
another suitable super-cold material.Do not sprayR-134a or R-12 refrigerant on the expansion
valve control head for this test.The suction (low
pressure) gauge reading should drop by 10 psi. If OK,
go to Step 7 If not OK, replace the faulty expansion
valve.
(7) Allow the expansion valve control head to thaw.
The suction (low pressure) gauge reading should sta-
bilize at 140 kPa to 240 kPa (20 psi to 30 psi). If not
OK, replace the faulty expansion valve.
(8) When expansion valve testing is complete, test
the overall air conditioner performance (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - A/C PERFORMANCE TEST).
Remove all test equipment before returning the vehi-
cle to service.
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 -
FRONT - WARNING - A/C PLUMBING), (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT - CAUTION - A/C PLUMBING), and (Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - WARNING - HEATER PLUMBING).
(1) Remove the rear HVAC housing from the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL).
(2) Carefully remove the foam insulator wrap from
the rear expansion valve.
(3) Remove the rear evaporator line extension from
the expansion valve (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EVAPORA-
TOR - REMOVAL - EVAPORATOR LINE EXTEN-
SION).
(4) Remove the two screws that secure the expan-
sion valve to the evaporator tube sealing plate.
(5) Remove the expansion valve from the evapora-
tor tubes.
(6) Remove the seals from the evaporator tube fit-
tings and discard.
(7) Install plugs in, or tape over the opened evap-
orator tube fittings and both expansion valve ports.
INSTALLATION
(1) Remove the tape or plugs from the rear A/C
evaporator tube fittings and both expansion valve
ports.
(2) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the rear evapora-
tor tube fittings.
(3) Position the expansion valve onto the evapora-
tor tubes.
24 - 100 PLUMBING - REARRS
A/C EXPANSION VALVE (Continued)

(4) Install the two screws that secure the rear A/C
expansion valve to the evaporator tube sealing plate.
Tighten the screws to 11 N´m (97 in. lbs.).
(5) Install the rear evaporator line extension onto
the expansion valve (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EVAPORA-
TOR - INSTALLATION - EVAPORATOR LINE
EXTENSION).
(6) Install the foam insulator wrap over the rear
expansion valve.
(7) Install the rear HVAC housing (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - INSTALLATION).
(8) Run the HVAC Cooldown Test to verify proper
operation.
HEATER CORE
DESCRIPTION
The rear heater core is located near the front of
the rear HVAC housing, behind the right rear wheel
house. It is a heat exchanger made of rows of tubes
and fins. One end of the core is fitted with a molded
plastic tank that includes integral heater core inlet
and outlet nipples. The rear heater core can be ser-
viced without removing the rear HVAC housing from
the vehicle.
OPERATION
Engine coolant is circulated through underbody
heater hoses to the rear heater core at all times. As
the coolant flows through the rear 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
rear blend door allows control of the rear heater out-
put air temperature by controlling how much of the
air flowing through the rear HVAC housing is
directed through the heater core.
The rear heater core cannot be repaired and, if
faulty or damaged, it must be replaced.
STANDARD PROCEDURE - REAR HEATER
CORE FILLING
In its final installed position, the rear heater core
is positioned higher than the radiator fill cap. There-
fore, when the cooling system is drained and refilled,
gravity will not refill the heater core with coolant to
the proper level. This may result in two problems:1.
Insufficient coolant level in the engine cooling sys-
tem, which may result in engine overheating.2.Air
entrapped within the rear heater core, which may
result in insufficient rear heater performance. There
are two methods that may be employed to prevent
these problems:1.Pre-filling of the rear heater core.2.Thermal cycling of the engine cooling system. Fol-
lowing are descriptions of both prevention methods,
as well as a method to verify rear heater perfor-
mance.
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING
FRONT - WARNING - HEATER PLUMBING).
PRE-FILLING
If the rear heater core or the rear HVAC housing
have been removed from the vehicle for service, the
rear heater core may be pre-filled with the proper
engine coolant mixture prior to reconnecting the
heater hoses to the heater core hose fittings.
(1) The heater core should be installed in the rear
HVAC housing, and the rear HVAC housing should
be installed in the vehicle.
(2) Take the proper precautions to protect the car-
peting below the rear heater core from spilled engine
coolant and have absorbent toweling readily avail-
able to mop up any spills.
(3) Insert the small end of an appropriate funnel
into the upper hose fitting of the heater core (Fig. 4).
(4) Carefully pour the proper pre-mixed engine
coolant solution into the rear heater core through a
funnel until coolant begins to appear at the lower
hose fitting of the heater core.
(5) Use absorbent toweling to clean up any engine
coolant spills from the preceding operation.
(6) Reconnect the heater hoses to the rear heater
core (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE - INSTAL-
LATION).
Fig. 4 Pre-Filling Heater Core - Typical
1 - REAR HEATER CORE
RSPLUMBING - REAR24 - 101
A/C EXPANSION VALVE (Continued)

(7) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
THERMAL CYCLING
If the rear heater core was emptied and was not
pre-filled, it will be necessary to thermal cycle the
vehicle at least two times to ensure that the rear
heater core is properly filled.
(1) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
(2) Start the engine and allow it to operate until
the thermostat opens.
(3) Turn the engine off and allow it to cool.
(4) With the engine cold and not running, check
and top off the engine coolant level as necessary
(Refer to 7 - COOLING - STANDARD PROCEDURE
- COOLANT LEVEL CHECK) and (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLANT
- ADDING).
(5) Start the engine and allow it to operate until
the thermostat opens again.
(6) Turn the engine off and allow it to cool down
again.
(7) With the engine cold and not running, check
and top off the engine coolant level as necessary
(Refer to 7 - COOLING - STANDARD PROCEDURE
- COOLANT LEVEL CHECK) and (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLANT
- ADDING).
(8) Check the performance of the rear heater.
Refer to REAR HEATER PERFORMANCE CHECK.
REAR HEATER PERFORMANCE CHECK
Successful completion of the rear heater perfor-
mance check will confirm that the rear heater core is
properly filled with engine coolant. If the check is not
successful, either there is still air trapped in the rear
heater core or the rear heater plumbing is restricted.
This check should be performed with the vehicle in a
shop where the ambient temperature is about 21É C
(70É F).
(1) Start the engine and allow it to idle until it
warms up to normal operating temperature.
(2) Adjust the heater-A/C controls so that the front
heater is turned Off, the rear heater is set for full
Heat, and the rear blower motor is at its highest
speed setting.
(3) Use an accurate test thermometer to measure
the temperature of the air being discharged from the
rear heater outlet located at the base of the right
C-pillar.
(4) Proper discharge air temperature readings
should be from 57É to 63É C (135É to 145É F).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
FRONT - WARNING - HEATER PLUMBING).
(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Remove the right quarter trim panel and right
D-pillar trim panel from the quarter inner panel
(Refer to 23 - BODY/INTERIOR/QUARTER TRIM
PANEL - REMOVAL).
(3) Remove the rear heater distribution duct from
the right quarter inner panel (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION -
REAR/REAR HEATER DISTRIBUTION DUCT -
REMOVAL).
(4) Remove the screw that secures the back of the
rear HVAC housing to the right D-pillar.
(5) Remove the screw that secures the front of the
rear HVAC housing to the right quarter inner panel.
(6) Take the proper precautions to protect the car-
peting below the rear heater core from spilled engine
coolant and have absorbent toweling readily avail-
able to mop up any spills.
(7) Disconnect the heater hoses at the rear heater
core (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE -
REMOVAL).
(8) Install plugs in, or tape over the opened heater
core fittings and both heater hoses (Fig. 5).
Fig. 5 Rear Heater Core
1 - REAR HVAC HOUSING OUTLET
2 - REAR HVAC UNIT HOUSING
3 - LATCH (4)
4 - REAR HEATER CORE
5 - RIGHT REAR WHEEL HOUSE
6 - REAR HEATER HOSES
24 - 102 PLUMBING - REARRS
HEATER CORE (Continued)