(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)
LIQUID 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 A/C liquid line is serviced in two
sections. The front section connects between the
A/C condenser and the receiver/drier and includes
the high side service port. The rear section con-
nects between the receiver/drier and the expansion
valve and includes the fitting for the A/C pressure
transducer. On models equipped with the optional
rear air conditioner, the rear section of the front air
conditioner liquid line also includes a liquid line
hose and tube extension that connects the front liq-
uid line to the liquid line for the rear air conditioner.
FRONT SECTION
(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 housing from the right
side of the engine compartment.
(4) Remove the two large screws that secure the
front fascia and the outboard ends of the radiator
sight shield to the radiator closure panel crossmem-
ber (Fig. 23).
(5) Remove the five small screws that secure the
front fascia grille inserts to the radiator sight shield.
(6) Remove the radiator sight shield from the radi-
ator closure panel crossmember.
(7) Remove the nut that secures the liquid line fit-
ting to the condenser on the right side of the cooling
module (Fig. 24).
(8) Disconnect the liquid line fitting from the A/C
condenser outlet port.
(9) Remove the O-ring seal and gasket from the
liquid line fitting and discard.
(10) Install plugs in, or tape over the opened liquid
line fitting and the condenser outlet port.
(11) Disengage the retainer that secures the liquid
line routing clip to the top of the right frame rail
ahead of the front strut tower in the engine compart-
ment (Fig. 25).(12) Remove the screw that secures the liquid line
front section fitting to the top of the receiver/drier.
(13) Disconnect the liquid line fitting from the
receiver/drier inlet port.
(14) Remove the seals from the liquid line fitting
and discard.
(15) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier inlet port.
(16) Remove the front section of the front liquid
line from the engine compartment.
Fig. 23 Radiator Sight Shield - Typical
1 - LARGE SCREWS (2)
2 - SMALL SCREWS (5)
3 - RADIATOR SIGHT SHIELD
4 - GRILLE INSERTS
5 - FRONT FASCIA
Fig. 24 A/C Condenser Connections
1 - A/C CONDENSER
2 - DISCHARGE LINE FITTING
3 - LIQUID LINE FITTING
4 - NUT
24 - 88 PLUMBING - FRONTRS
REAR SECTION
(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 housing from 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 A/C pressure transducer (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/A/C PRESSURE TRANSDUCER -
REMOVAL).
(6) If equipped, remove the nut that secures the
A/C ground strap to the weld stud on the top of the
right front strut tower (Fig. 25).
(7) If equipped, remove the A/C ground strap eye-
let terminal connector from the weld stud.(8) Remove the bolt that secures the liquid line
rear section fitting to the top of the receiver/drier.
(9) Disconnect the liquid line fitting from the
receiver/drier outlet port.
(10) Remove the O-ring seal from the liquid line
fitting and discard.
(11) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier outlet port.
(12) Remove the nut that secures the suction line
and liquid line fittings to the expansion valve.
(13) Disconnect the suction line and liquid line fit-
tings from the expansion valve.
(14) Remove the seals from the suction line and
liquid line fittings and discard.
(15) Install plugs in, or tape over the opened suc-
tion line and liquid line fittings and both expansion
valve ports.
(16) On RHD models, remove the liquid line from
the retaining bracket located at the top of the dash
panel
(17) If the vehicle is equipped with the optional
rear air conditioner, go to Step 18. If the vehicle does
not have the optional rear air conditioner, go to Step
24.
(18) Raise and support the vehicle.
(19) 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. 26).
(20) Disconnect the front liquid line extension fit-
ting from the underbody liquid line fitting for the
rear air conditioner.
(21) Remove the O-ring seal from the underbody
liquid line fitting and discard.
Fig. 25 Liquid Line - 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
Fig. 26 Underbody A/C Line Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - RETAINER STRAP (3)
4 - HEATER TUBES
5 - UNDERBODY REFRIGERANT LINES
RSPLUMBING - FRONT24-89
LIQUID LINE (Continued)
(22) Install plugs in, or tape over the opened liquid
line fittings.
(23) Lower the vehicle.
(24) Remove the front liquid line rear section from
the engine compartment.
INSTALLATION
FRONT SECTION
(1) Position the front section of the front liquid
line into the engine compartment.
(2) Remove the tape or plugs from the liquid line
front section fitting for the receiver/drier and the
receiver/drier inlet port.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(4) Reconnect the liquid line fitting to the receiver/
drier inlet port on the top of the receiver/drier.
(5) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 11 N´m
(97 in. lbs.).
(6) Engage the retainer that secures the liquid line
routing clip to the top of the right frame rail ahead of
the front strut tower in the engine compartment.
(7) Remove the tape or plugs from the A/C con-
denser outlet port and the liquid line fitting.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(9) Install a new dual plane seal and reconnect the
liquid line fitting to the condenser outlet port on the
right side of the cooling module.
(10) Install the nut that secures the liquid line fit-
ting to the condenser. Tighten the nut to 23 N´m (17
ft. lbs.).
(11) Position the radiator sight shield onto the
radiator closure panel crossmember.
(12) 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.).
(13) Install the two large screws that secure the
front fascia and the outboard ends of the radiator
sight shield to the radiator closure panel crossmem-
ber. Tighten the screws to 6 N´m (53 in. lbs.).
(14) Reinstall the air cleaner housing into the
right side of the engine compartment.
(15) Reconnect the battery negative cable.
(16) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(17) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).REAR SECTION
(1) Position the rear section of the front liquid line
into the engine compartment.
(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) Remove the tape or plugs from the liquid line
rear section fitting for the receiver/drier and the
receiver/drier outlet port.
(7) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(8) Reconnect the liquid line fitting to the receiver/
drier outlet port on the top of the receiver/drier.
(9) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 11 N´m
(97 in. lbs.).
(10) If equipped, reinstall the A/C ground strap
eyelet terminal connector onto the weld stud on the
top of the right front strut tower (if equipped).
(11) If equipped, install the nut that secures the
A/C ground strap to the weld stud. Tighten the nut
to 12 N´m (106 in. lbs.)
(12) Install the A/C pressure transducer (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/A/C PRESSURE TRANSDUCER - INSTAL-
LATION).
(13) Reconnect the drain tube to the wiper module
drain on the right side of the engine compartment.
(14) Reinstall the air cleaner housing into the
right side of the engine compartment.
(15) On RHD models, install the liquid line into
the retaining bracket located at the top of the dash
panel.
(16) If the vehicle is equipped with the optional
rear air conditioner, go to Step 17. If the vehicle does
not have the optional rear air conditioner, go to Step
23.
(17) Raise and support the vehicle.
(18) Remove the tape or plugs from the liquid line
rear section extension fitting and the underbody liq-
uid line fitting.
(19) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody liquid
line fitting.
(20) Reconnect the liquid line rear section exten-
sion fitting to the underbody liquid line fitting.
Tighten the fittings to 23 N´m (17 ft. lbs.).
24 - 90 PLUMBING - FRONTRS
LIQUID LINE (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)
(12) Remove the receiver/drier and mounting
bracket unit from the studs.
INSTALLATION
NOTE: If the receiver/drier is being replaced, add 25
milliliters (0.9 fluid ounce) of refrigerant oil to the
refrigerant system. Use only refrigerant oil of the
type recommended for the compressor in the vehi-
cle.
(1) Position the receiver/drier and mounting
bracket unit onto the weld studs on the side of the
right front strut tower.
(2) Install the two nuts that secure the receiver/
drier mounting bracket to the studs. Tighten the
nuts to 10 N´m (89 in. lbs.).
(3) Remove the tape or plugs from the liquid line
rear section fitting for the receiver/drier and the
receiver/drier outlet port.
(4) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(5) Reconnect the liquid line fitting to the receiver/
drier outlet port on the top of the receiver/drier.
(6) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 11 N´m
(97 in. lbs.).
(7) Remove the tape or plugs from the liquid line
front section fitting for the receiver/drier and the
receiver/drier inlet port.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(9) Reconnect the liquid line fitting to the receiver/
drier inlet port on the top of the receiver/drier.
(10) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 11 N´m
(97 in. lbs.).
(11) Reinstall the air cleaner housing into the
right side of the engine compartment.
(12) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(13) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
REFRIGERANT
DESCRIPTION
The refrigerant used in this air conditioning sys-
tem is a HydroFluoroCarbon (HFC), type R-134a.
Unlike R-12, which is a ChloroFluoroCarbon (CFC),
R-134a refrigerant does not contain ozone-depleting
chlorine. R-134a refrigerant is a non-toxic, non-flam-mable, clear, and colorless liquefied gas. Even though
R-134a does not contain chlorine, it must be
reclaimed and recycled just like CFC-type refriger-
ants. This is because R-134a is a greenhouse gas and
can contribute to global warming.
OPERATION
R-134a refrigerant is not compatible with R-12
refrigerant in an air conditioning system. Even a
small amount of R-12 added to an R-134a refrigerant
system will cause compressor failure, refrigerant oil
sludge or poor air conditioning system performance.
In addition, the PolyAlkylene Glycol (PAG) synthetic
refrigerant oils used in an R-134a refrigerant system
are not compatible with the mineral-based refriger-
ant oils used in an R-12 refrigerant system. R-134a
refrigerant system service ports, service tool couplers
and refrigerant dispensing bottles have all been
designed with unique fittings to ensure that an
R-134a system is not accidentally contaminated with
the wrong refrigerant (R-12). There are also labels
posted in the engine compartment of the vehicle and
on the compressor identifying to service technicians
that the air conditioning system is equipped with
R-134a.
REFRIGERANT OIL
DESCRIPTION
The refrigerant oil used in R-134a refrigerant sys-
tems is a synthetic-based, PolyAlkylene Glycol (PAG),
wax-free lubricant. Mineral-based R-12 refrigerant
oils are not compatible with PAG oils, and should
never be introduced to an R-134a refrigerant system.
There are different PAG oils available, and each con-
tains a different additive package. The compressor
used in this vehicle is designed to use an ND-8 PAG
refrigerant oil. Use only refrigerant oil of this same
type to service the refrigerant system.
OPERATION
After performing any refrigerant recovery or recy-
cling operation, always replenish the refrigerant sys-
tem with the same amount of the recommended
refrigerant oil as was removed. Too little refrigerant
oil can cause compressor damage, and too much can
reduce air conditioning system performance. PAG
refrigerant oil is much more hygroscopic than min-
eral oil, and will absorb any moisture it comes into
contact with, even moisture in the air. The PAG oil
container should always be kept tightly capped until
it is ready to be used. After use, recap the oil con-
tainer immediately to prevent moisture contamina-
tion.
24 - 92 PLUMBING - FRONTRS
RECEIVER / DRIER (Continued)
(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. 28).
(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. 29).
(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.
Fig. 28 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
Fig. 29 Underbody A/C Line Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - RETAINER STRAP (3)
4 - HEATER TUBES
5 - UNDERBODY REFRIGERANT LINES
RSPLUMBING - FRONT24-95
SUCTION LINE (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)