
CHARGING PROCEDURE
CAUTION: A small amount of refrigerant oil is
removed from the A/C system each time the refrig-
erant system is recovered and evacuated. Before
charging the A/C system, you MUST replenish any
oil lost during the recovery process. Refer the
equipment manufacturer instructions for more infor-
mation.
(1) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(2) A manifold gauge set and a R-134a refrigerant
recovery/recycling/charging station that meets SAE
Standard J2210 should still be connected to the
refrigerant system.
(3) Measure the proper amount of refrigerant and
heat it to 52É C (125É F) with the charging station.
See the operating instructions supplied by the equip-
ment manufacturer for proper use of this equipment.
(4) Open both the suction and discharge valves,
then open the charge valve to allow the heated
refrigerant to flow into the system.
(5) When the transfer of refrigerant has stopped,
close both the suction and discharge valves.
(6) If all of the refrigerant charge did not transfer
from the dispensing device, open all of the windows
in the vehicle and set the heater-air conditioner con-
trols so that the compressor is engaged and the
blower motor is operating at its lowest speed setting.
Run the engine at a steady high idle (about 1400
rpm). If the compressor will not engage, test the com-
pressor clutch control circuit and repair as required.
(7) Open the suction valve to allow the remaining
refrigerant to transfer to the refrigerant system.
WARNING: TAKE CARE NOT TO OPEN THE DIS-
CHARGE (HIGH PRESSURE) VALVE AT THIS TIME.
(8) Close the suction valve and test the system
performance. (Refer to 24 - HEATING & AIR CON-
DITIONING - STANDARD PROCEDURE - A/C PER-
FORMANCE TEST).
(9) Disconnect the charging station and manifold
gauge set from the refrigerant system service ports.
(10) Reinstall the caps onto the refrigerant system
service ports.
(11) Run the HVAC Control Cooldown test to ver-
ify proper operation(Refer to 24 - HEATING & AIR
CONDITIONING - DIAGNOSIS AND TESTING).A/C COMPRESSOR
DESCRIPTION
DESCRIPTION - A/C COMPRESSOR
Vehicles equipped with the 2.5L diesel, 3.3L and
3.8L gasoline engines use the Denso 10S20 A/C com-
pressor. Vehicles equipped with the 2.4L gasoline
engine use the Denso 10S17 A/C compressor. Both
A/C compressors include an integral high pressure
relief valve. The A/C compressor is secured to a
mounting bracket on the 2.4L gasoline engine and
directly to the cylinder block on the 2.5L diesel, 3.3L
and 3.8L gasoline engines.
DESCRIPTION - HIGH PRESSURE RELIEF
VALVE
A high pressure relief valve is located on the rear
of the A/C compressor. This mechanical valve is
designed to vent refrigerant from the A/C system to
protect against damage to the compressor and other
system components, caused by condenser air flow
restriction or an overcharge of refrigerant.
OPERATION
OPERATION - A/C COMPRESSOR
The A/C compressor is driven by the engine
through an electric clutch, drive pulley and belt
arrangement. The compressor is lubricated by refrig-
erant oil that is circulated throughout the refrigerant
system with the refrigerant.
The compressor draws in low-pressure refrigerant
vapor from the evaporator through its suction port. It
then compresses the refrigerant into a high-pressure,
high-temperature refrigerant vapor. The compressor
pumps the high-pressure refrigerant vapor to the
condenser through the compressor discharge port.
The compressor cannot be repaired. If faulty or
damaged, the entire compressor assembly must be
replaced. The compressor clutch, pulley and clutch
coil are available for service.
OPERATION - HIGH PRESSURE RELIEF VALVE
The high pressure relief valve vents the system
when a discharge pressure of 3445 to 4135 kPa (500
to 600 psi) or above is reached. The valve closes
when a minimum discharge pressure of 2756 kPa
(400 psi) is reached.
The high pressure relief valve vents only enough
refrigerant to reduce the system pressure, and then
re-seats itself. The majority of the refrigerant is con-
served in the system. If the valve vents refrigerant, it
does not mean that the valve is faulty.
RSPLUMBING - FRONT24-73
PLUMBING - FRONT (Continued)

The high pressure relief valve is a factory-cali-
brated unit. The valve cannot be adjusted or
repaired, and must not be removed or otherwise dis-
turbed. The valve is only serviced as a part of the
compressor assembly.
DIAGNOSIS AND TESTING - COMPRESSOR
NOISE DIAGNOSIS
Excessive noise while the air conditioning compres-
sor is operating can be caused by loose compressor
mounts, a loose compressor clutch, or high operating
pressures in the refrigerant system. Verify compres-
sor drive belt condition, proper compressor mounting,
correct refrigerant charge level, and compressor head
pressure before compressor repair is performed.
With the close tolerances within the compressor, it
is possible to experience a temporary lockup. The
longer the compressor is inactive, the more likely the
condition is to occur. This condition is the result of
normal refrigerant migration within the refrigerant
system caused by ambient temperature changes. The
refrigerant migration may wash the refrigerant oil
out of the compressor.
NOTE: Prior to a vehicle being removed from ser-
vice or stored for more than two weeks, the com-
pressor should be operated to ensure adequate
refrigerant oil distribution throughout the system
components. Turn on the air conditioner for a min-
imum of five minutes with outside air and the high-
est blower speed selected.
BELT NOISE
If the compressor drive belt slips at initial start-up,
it does not necessarily mean the compressor has
failed. The following procedure can be used to iden-
tify a compressor drive belt noise problem.
A. Start the vehicle and run at idle.
B. Turn the air conditioner On and listen for belt
squeal.
C. If belt squeal is heard, turn the air conditioner
Off immediately.
If the belt squeal stops when the air conditioner is
turned Off, perform the following repair procedures.
(1) Using an appropriate sized oil filter wrench or
a strap wrench, grasp the outer diameter of the com-
pressor clutch hub. While facing the compressor,
rotate the hub clockwise, then counterclockwise. If
the hub rotates, proceed to the next step. If the hub
will not rotate, the compressor is internally damaged,
and must be replaced.
(2) Turn the hub clockwise five complete revolu-
tions and remove the tool.
(3) Start the vehicle and run at idle.(4) Turn the air conditioner On. Observe the com-
pressor and the system for normal operation, noting
cooling performance and noise levels. Operate for five
minutes before turning the air conditioner Off. If
acceptable cooling performance is observed during
compressor operation, the compressor does not need
to be replaced.
(5) Inspect the drive belt for wear, damage, and
proper tension. (Refer to 7 - COOLING/ACCESSORY
DRIVE/DRIVE BELTS - DIAGNOSIS AND TEST-
ING).
REMOVAL
REMOVAL - COMPRESSOR
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) Disconnect and isolate the battery negative
cable.
(3) Remove the nut that secures the suction line
fitting to the top of the compressor.
(4) Disconnect the suction line fitting from the
compressor suction port.
(5) Remove the O-ring seal and gasket from the
suction line fitting and discard.
(6) Install plugs in, or tape over the opened suc-
tion line fitting and the compressor suction port.
(7) Remove the nut that secures the discharge line
fitting to the top of the compressor.
(8) Disconnect the discharge line fitting from the
compressor discharge port.
(9) Remove the O-ring seal and gasket from the
discharge line fitting and discard.
(10) Install plugs in, or tape over the opened dis-
charge line fitting and the compressor discharge port.
(11) Raise and support the vehicle.
(12) Remove the serpentine accessory drive belt
from the front of the engine (Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS).
(13) Disconnect the engine wire harness connector
from the compressor clutch coil pigtail wire connector
on the top of the compressor (Fig. 5) or (Fig. 6).
(14) On models with the 3.3L and 3.8L engines,
disengage the retainer on the engine wire harness
24 - 74 PLUMBING - FRONTRS
A/C COMPRESSOR (Continued)

compressor clutch coil take out from the bracket on
the top of the compressor.(15) On models with the 3.3L and 3.8L engines,
remove the two bolts and two nuts that secure the
compressor to the engine.
(16) On models with the 2.4L and 2.5L engine,
remove the four bolts that secure the compressor to
the mounting bracket on the engine (2.4L), or the cyl-
inder block (2.5L).
(17) Remove the A/C compressor from the engine
compartment.
NOTE: If a replacement compressor is being
installed, be certain to drain and measure the refrig-
erant oil contained in the removed compressor.
This will determine how much oil the replacement
compressor must contain before it is installed
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT/REFRIGERANT OIL - STAN-
DARD PROCEDURE - REFRIGERANT OIL LEVEL).
NOTE: The filter/drier should always be replaced
when the compressor is replaced. This will remove
any contaminants including moisture from the sys-
tem.
REMOVAL - A/C COMPRESSOR MOUNTING
BRACKET - 2.4L ENGINE
(1) Remove the A/C compressor from the mounting
bracket (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/COMPRESSOR - REMOVAL).
(2) Remove the four bolts that secure the compres-
sor mounting bracket to the engine (Fig. 7).
(3) Remove the compressor mounting bracket from
the engine.
Fig. 5 A/C Compressor - 2.4L Shown, 2.5L Typical
1 - CLUTCH COIL CONNECTOR
2 - DISCHARGE PORT
3 - A/C COMPRESSOR
4 - SUCTION PORT
5 - BOLT (4)
6 - A/C COMPRESSOR MOUNTING BRACKET
Fig. 6 A/C Compressor - 3.3L/3.8L Engine
1 - STUD
2 - CLUTCH COIL CONNECTOR
3 - DISCHARGE PORT
4 - BOLT (2)
5 - SUCTION PORT
6 - A/C COMPRESSOR
7 - STUD
8 - NUTS (2)
Fig. 7 Compressor Mounting Bracket - 2.4L Engine
1 - MOUNTING BRACKET
2 - BOLTS (4)
3 - ENGINE
RSPLUMBING - FRONT24-75
A/C COMPRESSOR (Continued)

INSTALLATION
INSTALLATION
NOTE: If a replacement A/C compressor is being
installed, be certain to check the refrigerant oil level
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT/REFRIGERANT OIL - STAN-
DARD PROCEDURE - REFRIGERANT OIL LEVEL).
Use only refrigerant oil of the type recommended
for the compressor in the vehicle.
NOTE: The filter/drier should always be replaced
when the compressor is replaced. This will remove
any contaminants including moisture from the sys-
tem.
(1) Position the A/C compressor into the engine
compartment.
(2) On models with the 2.4L and 2.5L engine,
loosely install the four bolts that secure the compres-
sor to the mounting bracket on the engine (2.4L), or
the cylinder block (2.5L). Tighten the bolts to 28 N´m
(21 ft. lbs.).
(3) On models with the 3.3L and 3.8L engines,
loosely install the two bolts and two nuts that secure
the compressor to the engine. Tighten each of the fas-
teners using the following sequence to 54 N´m (40 ft.
lbs.).
²The upper nut at the front of the compressor.
²The lower nut at the front of the compressor.
²The upper bolt at the rear of the compressor.
²The lower bolt at the rear of the compressor.
(4) On models with the 3.3L and 3.8L engines,
engage the retainer on the engine wire harness com-
pressor clutch coil take out to the bracket on the top
of the compressor.
(5) Connect the engine wire harness connector to
the compressor clutch coil pigtail wire connector on
the top of the compressor.
(6) Reinstall the serpentine accessory drive belt
(Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE
BELTS).
(7) Lower the vehicle.
(8) Remove the tape or plugs from the compressor
discharge port and the discharge line fitting.
(9) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the discharge line fit-
ting.
(10) Install a new gasket and reconnect the dis-
charge line fitting to the compressor discharge port.
(11) Install the nut that secures the discharge line
fitting to the compressor. Tighten the nut to 23 N´m
(17 ft. lbs.).
(12) Remove the tape or plugs from the compressor
suction port and the suction line fitting.(13) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the suction line fit-
ting.
(14) Install a new gasket and reconnect the suc-
tion line fitting to the compressor suction port.
(15) Install the nut that secures the suction line
fitting to the compressor. Tighten the nut to 23 N´m
(17 ft. lbs.).
(16) Reconnect the battery negative cable.
(17) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(18) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
INSTALLATION - A/C COMPRESSOR
MOUNTING BRACKET - 2.4L ENGINE
(1) Position the compressor mounting bracket onto
the engine.
(2) Install the four bolts that secure the compres-
sor mounting bracket to the engine. Tighten the bolts
to 54 N´m (40 ft. lbs.).
(3) Reinstall the A/C compressor onto the mount-
ing bracket (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/COMPRESSOR -
INSTALLATION).
A/C CONDENSER
DESCRIPTION
The A/C condenser is integral to a cooling module
which includes the radiator, the electric cooling fan,
the fan shroud, air seals and an automatic transmis-
sion oil cooler. The cooling module is located in the
air flow in the front of the engine compartment
behind the radiator grille. The A/C condenser is a
heat exchanger that allows the high-pressure refrig-
erant gas being discharged from the compressor to
give up its heat to the air passing over the condenser
fins. The A/C condenser may be removed from the
cooling module for service without removing the cool-
ing module from the vehicle.
OPERATION
When the refrigerant gas gives up its heat, it con-
denses. When the refrigerant leaves the condenser, it
has become a high-pressure liquid refrigerant. The
volume of air flowing over the condenser fins is crit-
ical to the proper cooling performance of the air con-
ditioning system. Therefore, it is important that
there are no objects placed in front of the radiator
grille openings in the front of the vehicle or foreign
24 - 76 PLUMBING - FRONTRS
A/C COMPRESSOR (Continued)

(18) Install plugs in, or tape over the opened suc-
tion line fittings.
(19) Lower the vehicle.
(20) 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 front expansion valve.
Tighten the nut to 23 N´m (17 ft. lbs.).
(6) Engage 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) Reconnect the suction line fitting to the com-
pressor 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) Reinstall the air cleaner top cover and snorkel
onto the air cleaner housing located on the right side
of the engine compartment.
(13) Reconnect the battery negative cable.
(14) Raise and support the vehicle.
(15) Remove the tape or plugs from the suction
line extension fitting and the underbody suction line
fitting.(16) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody suction
line fitting.
(17) Reconnect the suction line extension fitting to
the underbody suction line fitting. Tighten the fitting
to 23 N´m (17 ft. lbs.).
(18) 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.
(19) Lower the vehicle.
(20) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(21) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
UNDERBODY LINES
DESCRIPTION
The underbody heater-A/C plumbing is used only
on models with the optional rear heater-A/C system
(Fig. 11). The underbody suction line, liquid line, and
heater tubes can each be serviced separately.
OPERATION
The rear heater and A/C lines are all serviced as
individual pieces. When disconnecting any line or
block ensure that the area around it is clean of any
contaminations that can get in to the system (Fig.
12), (Fig. 13), (Fig. 15), (Fig. 14) and (Fig. 16).
Any kinks or sharp bends in the rear heater-A/C
unit plumbing will reduce the capacity of the entire
heating and air conditioning system. Kinks and
sharp bends reduce the system flow. High pressures
are produced in the refrigerant system when the air
conditioning compressor is operating. High tempera-
ture coolant is present in the heater plumbing when
the engine is operating. Extreme care must be exer-
cised o make sure that each of the plumbing connec-
tions is pressure-tight and leak free.
RSPLUMBING - REAR24 - 107
SUCTION LINE (Continued)

REMOVAL
REMOVAL - UNDERBODY HEATER TUBES
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) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Raise and support vehicle.
(3) Disconnect the underbody heater tubes at the
rear of the vehicle by releasing the insert in the rear
underbody heater tube quick connect fittings (Fig.17) and carefully pulling downward on the inlet and
return tubes.
(4) Remove the three retaining straps that secure
the rear heater underbody tubes to the vehicle under-
body (Fig. 18).
(5) Lower the rear of the underbody heater tubes
and drain any residual coolant from the tubes into a
suitable container.
(6) Using spring tension clamp pliers, compress
and slide the clamps off of the rubber hoses at the
front of the underbody heater tubes.
CAUTION:
DO NOT apply excessive pressure on heater tubes
or connections when removing heater hoses.
Excessive pressure may damage or deform the
tubes, causing an engine coolant leak.
(7) Disconnect the front underbody heater inlet
and return hoses by carefully twisting the hoses back
and forth on the underbody tubes, while gently pull-
ing them away from the end of the tubes.
(8) If necessary, carefully cut the hose ends and
peel the hoses off of the tubes.
NOTE:
Replacement of the heater hoses will be required if
the hose ends are cut for removal.
(9) Remove the underbody heater tubes from the
vehicle.
Fig. 15 Rear heater hose quick connects
1 - INSERT
2 - QUICK CONNECT FITTING
3 - COMPRESS INSERT FOR REMOVAL
Fig. 16 Rear A/C Block Connection
1 - CLEAN AREA AROUND BLOCK BEFORE REMOVAL
Fig. 17 Underbody Heater Tube Quick Connect
Fittings
1 - INSERT
2 - QUICK CONNECT FITTING
3 - COMPRESS INSERT FOR REMOVAL
RSPLUMBING - REAR24 - 109
UNDERBODY LINES (Continued)

NATURAL VAC LEAK
DETECTION ASSY
REMOVAL
(1) Disconnect thew negative battery cable.
(2) Raise vehicle and support (Fig. 4).
(3) Unlock and disconnect the electrical connector.
(4) Remove the hoses from the NVLD valve.
(5) Remove the 2 fasteners.
(6) Remove the valve and bracket from vehicle
(Fig. 5).
(7) Remove valve from bracket (Fig. 6).
INSTALLATION
(1) Install NVLD valve to the bracket (Fig. 6).
(2) Install valve and bracket to the vehicle (Fig. 5).
(3) Install the 2 mounting bolts and tighten.
(4) Install the electrical connector and lock.
(5) Install the 2 hoses and lock the clamps.
(6) Lower vehicle.
LEAK DETECTION PUMP
REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Remove 3 hoses (Fig. 7).
(4) Remove the electrical connector (Fig. 8).
(5) Remove the 3 screws and remove LDP pump.
INSTALLATION
(1) Install LDP.
(2) Install the 3 screws and tighten (Fig. 8).
(3) Install the electrical connector.
(4) Install the 3 hoses (Fig. 7).
(5) Lower vehicle.
(6) Connect the negative battery cable.
Fig. 4 NVLD LOCATION
Fig. 5 NVLD REMOVAL/INSTALLATION
Fig. 6 NVLD VALVE AND BRACKET
RSEVAPORATIVE EMISSIONS25-13

DIAGNOSIS AND TESTING - PCV SYSTEM
WARNING: APPLY PARKING BRAKE AND/OR
BLOCK WHEELS BEFORE PERFORMING ANY TEST
OR ADJUSTMENT WITH THE ENGINE OPERATING.
(1) With engine idling, remove the hose from the
PCV valve. If the valve is not plugged, a hissing
noise will be heard as air passes through the valve. A
strong vacuum should also be felt when a finger is
placed over the valve inlet.
(2) Install hose on PCV valve. Remove the
make-up air hose from the air plenum at the rear of
the engine. Hold a piece of stiff paper (parts tag)
loosely over the end of the make-up air hose.
(3) After allowing approximately one minute for
crankcase pressure to reduce, the paper should draw
up against the hose with noticeable force. If the
engine does not draw the paper against the grommet
after installing a new valve, replace the PCV valve
hose.
(4) Turn the engine off. Remove the PCV valve
from intake manifold. The valve should rattle when
shaken.
(5) Replace the PCV valve and retest the system if
it does not operate as described in the preceding
tests.Do not attempt to clean the old PCV valve.
If the valve rattles, apply a light coating of Loctitet
Pipe Sealant With Teflon to the threads. Thread the
PCV valve into the manifold plenum and tighten to 7
N´m (60 in. lbs.) torque.
Fig. 10 PCV VALVE 2.4L
1 - PCV Valve
Fig. 11 PCV VALVE 3.3/3.8L
Fig. 12 Engine Off or Engine Backfire No Vapor
Flow
Fig. 13 High Intake Manifold Vacuum Minimal Vapor
Flow
Fig. 14 Moderate Intake Manifold Vacuum Maximum
Vapor Flow
RSEVAPORATIVE EMISSIONS25-17
PCV VALVE (Continued)