coolant CHRYSLER CARAVAN 2005 Service Manual

TEMPERATURE CONTROL
If the heater outlet air temperature cannot be
adjusted with the temperature control knob on the
A/C-heater control panel, the following could require
service:
²Blend door binding.
²Faulty blend door actuator.
²Faulty A/C-heater control.
²Faulty related wiring harness or connectors.²Improper engine coolant temperature.
SPECIFICATIONS
A/C SYSTEM
The R-134a refrigerant system charge capacity for
this vehicle can be found on the underhood Specifica-
tion Label.
SYSTEM SPECIFICATIONS
Item Description Notes
A/C Compressor Denso 10S17 ± 2.4L/2.5L/2.8L/3.3L
without rear A/C
Denso 10S20 ± 3.3L/3.8L with rear
A/CND-8 PAG Oil
Freeze±up Control Evaporator temperature sensor HVAC housing mounted (RS models),
Evaporator mounted (RG models) - input to
A/C-heater control module
Low PSI Control A/C pressure transducer Liquid line mounted - input to Powertrain Control
Module (PCM) - PCM opens compressor clutch
relay above 200 kPa (29 psi)
High PSI Control A/C pressure transducer Liquid line mounted - input to PCM - PCM
opens compressor clutch relay below 3100 kPa
(450 psi)
High Pressure relief valve Compressor mounted - opens above 3445-4135
kPa (500-600 psi), closes below 2756 kPa (400
psi)
Compressor Clutch Coil
DrawDenso 10S17 ± 3.3 amps @ 12V  
0.5V @ 21É C (70É F)
Denso 10S20 ± 2.2 amps @ 12V  
0.5V @ 21É C (70É F)
Compressor Clutch Air
Gap0.35 - 0.60 mm (0.014 - 0.024 in.)
TORQUE SPECIFICATIONS
Description N´m Ft. Lbs. In. Lbs.
A/C Compressor Shaft Bolt 17.5 ± 155
A/C Compressor Mounting Bolts (2.4L/2.5L/2.8L) 28 21 ±
A/C Compressor Mounting Bolts (3.3L/3.8L) 54 40 ±
A/C Compressor Mounting Bracket Bolts (2.4L) 54 40 ±
A/C Condenser Mounting Bracket Screws 5 ± 45
A/C Expansion Valve Screws 11 ± 97
A/C-Heater Control Screws 2 ± 17
Blend Door Actuator Screws 2 ± 17
Blower Motor Screws 2 ± 17
Blower Motor Power Module Screws (ATC) 2 ± 17
Blower Motor Resistor Block Screws (MTC) 2 ± 17
Center Bezel Outlet Screws 2 ± 17
RSHEATING & AIR CONDITIONING24-11
HEATING & AIR CONDITIONING (Continued)

(13) Remove the two screws that secure the top of
the quarter trim panel attaching bracket to the quar-
ter inner panel.(14) Remove the two screws that secure the bottom
of the quarter trim panel attaching bracket to the
rear HVAC housing.
(15) Remove the rear floor heat duct from the
right quarter inner panel (Refer to 24 - HEATING &
AIR CONDITIONING/DISTRIBUTION/REAR
FLOOR HEAT DUCT - REMOVAL).
(16) Take the proper precautions to protect the
carpeting below the rear heater core from spilled
engine coolant and have absorbent toweling readily
available to clean up any spills.
(17) Disconnect the heater hoses at the rear heater
core (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE -
REMOVAL).
(18) Install plugs in, or tape over the opened
heater core fittings and both heater hoses.
(19) Use absorbent toweling to mop up any engine
coolant spills from the preceding operation.
(20) Remove the screw that secures the back of the
rear HVAC housing to the right D-pillar (Fig. 8).
(21) Remove the screw that secures the front of
the rear HVAC housing to the right quarter inner
panel.
(22) Lift the rear HVAC housing up far enough for
the lower mounting studs and the evaporator exten-
sion lines to clear the mounting holes in the rear
floor panel.
(23) Remove the rear HVAC housing from the
vehicle.
(24) Use absorbent toweling to mop up any engine
coolant spills from the preceding operation.
Fig. 5 Underbody A/C Line Rear Connections ± with
New Seating Element (NSE)
1 - UNDERBODY LIQUID LINE
2 - NUT
3 - SEALING PLATE
4 - UNDERBODY SUCTION LINE
5 - EXTENSION LINE TAPPING PLATE
Fig. 6 Underbody A/C Line Rear Connections ±
without New Seating Element (NSE)
1 - UNDERBODY LIQUID LINE
2 - BOLT
3 - EXTENSION LINE TAPPING PLATE
4 - UNDERBODY SUCTION LINE
5 - SEALING PLATE
Fig. 7 Rear HVAC Housing Mounting Studs ±
Typical
1 - REAR HVAC HOUSING MOUNTING STUDS
RSDISTRIBUTION - REAR24-61
HVAC HOUSING (Continued)

INSTALLATION
NOTE: 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 recon-
necting the heater hoses to the heater core hose fit-
tings (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - REAR/HEATER CORE - STANDARD
PROCEDURE - HEATER CORE FILLING).
(1) Position the rear HVAC housing into the vehi-
cle with the evaporator extension line sealing plate
inserted into the rectangular hole in the rear floor
panel behind the right rear wheel house.
(2) Align the rear HVAC housing lower mounting
studs with the holes in the rear floor panel and lower
the rear HVAC housing to the floor.
(3) Install the screw that secures the front of the
rear HVAC housing to the right quarter inner panel.
Tighten the screw to 11 N´m (97 in. lbs.).(4) Install the screw that secures the back of the
rear HVAC housing to the right D-pillar. Tighten the
screw to 11 N´m (97 in. lbs.).
(5) Remove the plugs or tape from both heater core
fittings and both heater hoses.
(6) Reconnect the heater hoses to the rear heater
core (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE - INSTAL-
LATION).
(7) Reinstall the rear floor heat duct onto the right
quarter inner panel (Refer to 24 - HEATING & AIR
CONDITIONING/DISTRIBUTION/REAR FLOOR
HEAT DUCT - INSTALLATION).
(8) Install the two screws that secure the bottom
of the quarter trim panel attaching bracket to the
rear HVAC housing. Tighten the screws to 2 N´m (17
in. lbs.).
(9) Install and tighten the two screws that secure
the top of the quarter trim panel attaching bracket to
the quarter inner panel.
Fig. 8 Rear HVAC Housing ± Typical
1 - U-NUT (3)
2 - REAR HVAC HOUSING
3 - SCREW (3)
4 - EXPANSION VALVE5 - STUD (2 w/NSE, 3 wo/NSE)
6 - HEATER LINES
7 - NUT (5)
8 - STUD (2)
24 - 62 DISTRIBUTION - REARRS
HVAC HOUSING (Continued)

PLUMBING - FRONT
DESCRIPTION
CAUTION: The system must be completely empty
before opening any fitting or connection in the
refrigeration system. Open fittings with caution
even after the system has been emptied. If any
pressure is noticed as a fitting is loosened,
retighten fitting and evacuate the system again.
The use of correct wrenches when making connec-
tions is very important. Improper wrenches or
improper use of wrenches can damage the fittings.
The internal parts of the A/C system will remain sta-
ble as long as moisture-free refrigerant and refrig-
erant oil is used. Abnormal amounts of dirt,
moisture or air can upset the chemical stability.
This may cause operational troubles or even seri-
ous damage if present in more than very small
quantities. Before disconnecting a refrigerant line
or hose, clean the outside of the fittings thoroughly
to prevent contamination from entering the refriger-
ant system.
When opening a refrigeration system, have every-
thing you will need to repair the system ready to
minimize the amount of time the system is opened.
Cap or plug all refrigerant line fittings as soon as
they are opened. This will help prevent the entrance
of dirt and moisture. All new lines and components
should be capped or sealed until they are ready to
be used. Before connecting a refrigerant line or
hose, clean the outside of the fittings thoroughly to
prevent contamination from entering the refrigerant
system.
All tools, including the refrigerant dispensing mani-
fold, manifold gauge set and test hoses should be
kept clean and dry.
The A/C refrigerant lines and hoses are used to
carry the refrigerant between the various A/C system
components. The refrigerant lines and hoses for the
R-134a system on this vehicle consist of a barrier-
hose design with a nylon tube sandwiched between
rubber layers. The nylon tube helps to contain the
R-134a refrigerant, which has a smaller molecular
structure than R-12 refrigerant. The ends of the
refrigerant lines are made from lightweight alumi-
num or steel, and commonly use braze-less fittings.Any kinks or sharp bends in the refrigerant lines
and hoses will reduce the capacity of the entire A/C
system and can reduce the flow of refrigerant in the
system. The radius of all bends in the flexible hose
refrigerant lines should be at least ten times the
diameter of the hose and the refrigerant lines should
be routed so they are at least 80 millimeters (3
inches) away from the exhaust manifold(s) and
exhaust pipe(s).
OPERATION
High pressures are produced in the refrigerant sys-
tem when the A/C compressor is operating. Extreme
care must be exercised to make sure that each of the
refrigerant system connections is pressure-tight and
leak free. It is a good practice to inspect all flexible
hose refrigerant lines at least once a year to make
sure they are in good condition and properly routed.
The refrigerant lines and hoses are coupled to
other A/C system components with block-type fit-
tings. An O-ring seal, or a flat steel gasket with an
integral O-ring (dual plane seal), is used to mate the
refrigerant line fittings with A/C system components
to ensure the integrity of the refrigerant system.
The refrigerant lines and hoses cannot be repaired
and, if faulty or damaged, they must be replaced.
WARNING
ENGINE COOLING SYSTEM
WARNING: THE ENGINE COOLING SYSTEM IS
DESIGNED TO DEVELOP INTERNAL PRESSURES
OF 97 TO 123 KILOPASCALS (14 TO 18 POUNDS
PER SQUARE INCH). DO NOT REMOVE OR
LOOSEN THE COOLANT PRESSURE CAP, CYLIN-
DER BLOCK DRAIN PLUGS, RADIATOR DRAIN,
RADIATOR HOSES, HEATER HOSES, OR HOSE
CLAMPS WHILE THE ENGINE COOLING SYSTEM IS
HOT AND UNDER PRESSURE. FAILURE TO
OBSERVE THIS WARNING CAN RESULT IN SERI-
OUS BURNS FROM THE HEATED ENGINE COOL-
ANT. ALLOW THE VEHICLE TO COOL FOR A
MINIMUM OF 15 MINUTES BEFORE OPENING THE
COOLING SYSTEM FOR SERVICE.
RSPLUMBING - FRONT24-65

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 door
allows 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
FRONT 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. 17).
(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.
(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.
Fig. 17 Heater Core Tubes - LHD Shown, RHD
Typical
1 - SEAL
2 - HEATER CORE TUBES
3 - SCREW
4 - HEATER CORE
5 - DISTRIBUTION HOUSING
6 - SEALING PLATE
24 - 84 PLUMBING - FRONTRS
HEATER CORE (Continued)

FRONT 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. 18) and pushing the brake pedal downward
(Fig. 19) 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.
INSTALLATION
FRONT 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.
Fig. 18 Accelerator Pedal - LHD Shown, RHD Typical
1 - HEATER CORE
Fig. 19 Brake Pedal - LHD Shown, RHD Typical
1 - HEATER CORE
2 - BRAKE PEDAL
RSPLUMBING - FRONT24-85
HEATER CORE (Continued)

(2) Using spring tension clamp pliers, compress
and slide the clamps off of each end of the hose being
removed (Fig. 20), (Fig. 21) or (Fig. 22).
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.
INSTALLATION
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).
(1) Using spring tension clamp pliers, compress
and slide each clamp away from the end of the hose
being installed.(2) Install each hose by carefully twisting the hose
back and forth while gently pushing it onto the tube
or nipple end.
(3) Using spring tension clamp pliers, compress
and slide the clamps onto each end of the hose being
installed.
(4) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
Fig. 20 Heater Inlet Hose - 2.4L Shown, 2.5L Typical
1 - ENGINE OUTLET NIPPLE
2 - HEATER INLET HOSE
3 - HEATER CORE OUTLET
4 - HEATER CORE INLET
5 - SCREW
6 - HEATER TUBE
7 - HEATER RETURN HOSE
8 - ENGINE INLET NIPPLE
Fig. 21 Heater Inlet Hose - 3.3L/3.8L W/O Rear
Heater
1 - ENGINE OUTLET NIPPLE
2 - HEATER CORE OUTLET
3 - HEATER CORE INLET
4 - HEATER RETURN TUBE (TYPICAL)
Fig. 22 Heater Inlet Hose - 3.3L/3.8L With Rear
Heater
1 - STUD
2 - HEATER CORE OUTLET
3 - HEATER CORE INLET
4 - TO ENGINE OUTLET NIPPLE
5 - TO UNDERBODY PLUMBING
6 - TO HEATER RETURN TUBE & HOSE
RSPLUMBING - FRONT24-87
HEATER INLET HOSE (Continued)

HEATER RETURN 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 return tube 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. 23), (Fig. 24) or (Fig. 25).
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 return 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.
Fig. 23 Heater Return Hose - 2.4L Shown, 2.5L
Typical
1 - ENGINE OUTLET NIPPLE
2 - HEATER INLET HOSE
3 - HEATER CORE OUTLET
4 - HEATER CORE INLET
5 - SCREW
6 - HEATER TUBE
7 - HEATER RETURN HOSE
8 - ENGINE INLET NIPPLE
Fig. 24 Heater Return Hose - 3.3L/3.8L W/O Rear
Heater
1 - ENGINE OUTLET NIPPLE
2 - HEATER CORE OUTLET
3 - HEATER CORE INLET
4 - HEATER RETURN TUBE (TYPICAL)
24 - 88 PLUMBING - FRONTRS

(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)