2005 CHRYSLER CARAVAN heater

CAUTION: A valve core that is not fully seated in
the A/C service port can result in damage to the
valve during refrigerant system evacuation and
charge. Such damage may result in a loss of sys-
tem refrigerant while uncoupling the charge adapt-
ers.
(4) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(5) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
(6) Reinstall the protective cap onto the A/C ser-
vice port.
SUCTION LINE
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).
NOTE: The front suction line includes the low side
service port on a section of tubing located near the
A/C compressor. On models equipped with the
optional rear A/C system, the front suction line also
includes a suction line hose and tube extension
that connects the front suction line to the suction
line for the rear A/C system.
(1) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the air cleaner top cover and snorkel
from the air cleaner housing located on the right side
of the engine compartment.
(4) Disconnect the drain tube from the wiper mod-
ule drain on the right side of the engine compart-
ment.
(5) Remove the nut that secures the suction line
fitting to the top of the A/C compressor.
(6) Disconnect the suction line fitting from the
compressor suction port.(7) Remove the O-ring seal from the suction line
fitting and discard.
(8) Install plugs in, or tape over the opened suc-
tion line fitting and the compressor suction port.
(9) Remove the retainer that secures the suction
line routing clip to the receiver/drier mounting
bracket on the side of the right front strut tower in
the engine compartment (Fig. 31).
(10) Remove the nut that secures the suction line
and liquid line fittings to the expansion valve.
(11) Disconnect the suction line and liquid line fit-
tings from the expansion valve.
(12) Remove the seals from the suction line and
liquid line fittings and discard.
(13) Install plugs in, or tape over the opened suc-
tion line and liquid line fittings and both expansion
valve ports.
(14) Remove the suction line from the retaining
bracket located at the top of the dash panel.
(15) If the vehicle is equipped with the optional
rear air conditioner, go to Step 16. If the vehicle does
not have the optional rear air conditioner, go to Step
22.
(16) Raise and support the vehicle.
(17) Cut the tie strap located just forward of the
connections between the underbody plumbing and
the engine compartment plumbing for the rear
heater and air conditioner (Fig. 32).
Fig. 31 Suction Line - LHD Shown, RHD Typical
1 - A/C EXPANSION VALVE
2 - SUCTION LINE EXTENSION (REAR A/C ONLY)
3 - NUT
4 - RETAINING CLIP
5 - SUCTION LINE
24 - 96 PLUMBING - FRONTRS
SERVICE PORT VALVE CORE (Continued)

(18) Disconnect the suction line extension fitting
from the underbody suction line fitting for the rear
air conditioner.
(19) Remove the O-ring seal from the underbody
suction line fitting and discard.
(20) Install plugs in, or tape over the opened suc-
tion line fittings.
(21) Lower the vehicle.
(22) Remove the suction line from the engine com-
partment.
INSTALLATION
(1) Position the suction line into the engine com-
partment.
(2) Remove the tape or plugs from the suction line
and liquid line fittings and both expansion valve
ports.
(3) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the suction line
and liquid line fittings.
(4) Reconnect the liquid line and suction line fit-
tings to the expansion valve.
(5) Install the nut that secures the suction line
and liquid line fittings to the expansion valve.
Tighten the nut to 23 N´m (17 ft. lbs.).
(6) Install the retainer that secures the suction
line routing clip to the receiver/drier mounting
bracket on the side of the right front strut tower in
the engine compartment.(7) Remove the tape or plugs from the compressor
suction port and the suction line fitting.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the suction line fit-
ting.
(9) Install a new dual plan seal and reconnect the
suction line fitting to the compressor suction port.
(10) Install the nut that secures the suction line
fitting to the A/C compressor. Tighten the nut to 23
N´m (17 ft. lbs.).
(11) Reconnect the drain tube to the wiper module
drain on the right side of the engine compartment.
(12) Install the air cleaner top cover and snorkel
onto the air cleaner housing located on the right side
of the engine compartment.
(13) On RHD models, install the suction line into
the retaining bracket located at the top of the dash
panel.
(14) If the vehicle is equipped with the optional
rear air conditioner, go to Step 15. If the vehicle does
not have the optional rear air conditioner, go to Step
21.
(15) Raise and support the vehicle.
(16) Remove the tape or plugs from the suction
line extension fitting and the underbody suction line
fitting.
(17) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody suction
line fitting.
(18) Reconnect the suction line extension fitting to
the underbody suction line fitting. Tighten the fit-
tings to 23 N´m (17 ft. lbs.).
(19) 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.
(20) Lower the vehicle.
(21) Reconnect the battery negative cable.
(22) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(23) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
Fig. 32 Underbody A/C Line Connections
1 - SUCTION LINE EXTENSION TUBE
2 - LIQUID LINE EXTENSION TUBE
3 - RETAINING STRAP
4 - REAR HEATER EXTENSION TUBES
5 - UNDERBODY REFRIGERANT LINES
RSPLUMBING - FRONT24-97
SUCTION LINE (Continued)

PLUMBING - REAR
TABLE OF CONTENTS
page page
A/C EVAPORATOR
DESCRIPTION.........................98
OPERATION...........................98
REMOVAL
REAR A/C EVAPORATOR...............98
REAR A/C EVAPORATOR LINE
EXTENSION.........................99
INSTALLATION
REAR A/C EVAPORATOR..............100
REAR A/C EVAPORATOR LINE
EXTENSION........................100
A/C EXPANSION VALVE
DESCRIPTION........................100
OPERATION..........................100
DIAGNOSIS AND TESTING
REAR A/C EXPANSION VALVE..........101
REMOVAL............................101
INSTALLATION........................101
HEATER CORE
DESCRIPTION........................102
OPERATION..........................102
STANDARD PROCEDURE
REAR HEATER CORE FILLING..........102REMOVAL............................103
INSTALLATION........................104
HEATER HOSES
REMOVAL............................104
INSTALLATION........................105
LIQUID LINE
REMOVAL............................105
INSTALLATION........................106
SUCTION LINE
REMOVAL............................106
INSTALLATION........................107
UNDERBODY LINES
DESCRIPTION........................108
OPERATION..........................108
REMOVAL
UNDERBODY HEATER TUBES..........109
UNDERBODY REFRIGERANT LINES......110
INSTALLATION
UNDERBODY HEATER TUBES..........112
UNDERBODY REFRIGERANT LINES......112
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
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-
24 - 98 PLUMBING - REARRS

TIONING/PLUMBING - REAR/EXPANSION VALVE
- REMOVAL).
(4) Remove the rubber grommet that seals the
evaporator inlet and outlet tubes to the rear HVAC
housing near the expansion valve.
(5) Remove the three screws that secure the upper
half of the rear HVAC housing to the lower half (Fig.
1).
(6) Remove the three metal spring clips that
secure the upper half of the rear HVAC housing to
the lower half.
(7) Carefully separate and remove the upper half
of the rear HVAC housing from the lower half.
(8) Remove the A/C evaporator from the lower half
of the rear HVAC housing.
REAR A/C EVAPORATOR LINE EXTENSION
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 screw that secures the plate that
captures and seals the evaporator line extension
within the base of the rear HVAC housing (Fig. 2).
(3) Remove the capture plate from the rear HVAC
housing base.(4) Carefully peel back the expansion valve foam
insulator wrap far enough to access the evaporator
line extension sealing plate on the bottom of the
expansion valve (Fig. 3).
(5) Remove the two screws that secure the expan-
sion valve bracket to the lower rear HVAC housing.
(6) Remove the nut that secures the expansion
valve bracket to the expansion valve stud.
(7) Remove the expansion valve bracket from the
expansion valve stud.
(8) Remove the nut that secures the evaporator
line extension seal plate to the expansion valve stud.
Fig. 1 Rear A/C Evaporator
1 - UPPER REAR HVAC HOUSING
2 - REAR A/C EVAPORATOR
3 - LOWER REAR HVAC HOUSING
Fig. 2 Evaporator Line Extension Plate
1 - REAR HVAC HOUSING BASE
2 - PLATE
3 - EVAPORATOR LINE EXTENSION
Fig. 3 Rear A/C Evaporator Line Extension
1 - UPPER REAR HVAC HOUSING
2 - LOWER REAR HVAC HOUSING
3 - EXPANSION VALVE BRACKET
4 - EVAPORATOR LINE EXTENSION
5 - EXPANSION VALVE STUD
6 - INSULATOR WRAP
RSPLUMBING - REAR24-99
A/C EVAPORATOR (Continued)

(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
REAR A/C EVAPORATOR
NOTE: If the rear A/C evaporator is being replaced,
add 50 milliliters (1.7 fluid ounces) of refrigerant oil
to the refrigerant system. Use only refrigerant oil of
the type recommended for the A/C 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).
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.
The rear A/C expansion valve cannot be adjusted
or repaired and, if faulty or damaged, it must be
replaced.
24 - 100 PLUMBING - REARRS
A/C EVAPORATOR (Continued)

DIAGNOSIS AND TESTING
REAR A/C 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 suit-
able super-cold material.Do not spray R-134a or
R-12 refrigerant on the expansion valve controlhead 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.
(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.).
RSPLUMBING - REAR24 - 101
A/C EXPANSION VALVE (Continued)

(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
24 - 102 PLUMBING - REARRS
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
RSPLUMBING - REAR24 - 103
HEATER CORE (Continued)