DIAGNOSIS AND TESTING - COMMON
PROBLEM CAUSES
The majority of transaxle malfunctions are a result
of:
²Insufficient lubrication
²Incorrect lubricant
²Misassembled or damaged internal components
²Improper operation
HARD SHIFTING
Hard shifting may be caused by a misadjusted
crossover cable. If hard shifting is accompanied by
gear clash, synchronizer clutch and stop rings or gear
teeth may be worn or damaged.
Hard shifting may also be caused by a binding or
broken shift cover mechanism. Remove shift cover
and verify smooth operation. Replace as necessary.
Misassembled synchronizer components also cause
shifting problems. Incorrectly installed synchronizer
sleeves, keys, balls, or springs can cause shift prob-
lems.
NOISY OPERATION
Transaxle noise is most often a result of worn or
damaged components. Chipped, broken gear or syn-
chronizer teeth, and brinnelled, spalled bearings all
cause noise.
Abnormal wear and damage to the internal compo-
nents is frequently the end result of insufficient
lubricant.
SLIPS OUT OF GEAR
Transaxle disengagement may be caused by mis-
aligned or damaged shift components, or worn teeth
on the drive gears or synchronizer components. Incor-
rect assembly also causes gear disengagement. Check
for missing snap rings.
LOW LUBRICANT LEVEL
Insufficient transaxle lubricant is usually the
result of leaks, or inaccurate fluid level check or refill
method. Leakage is evident by the presence of oil
around the leak point. If leakage is not evident, the
condition is probably the result of an underfill.
If air±powered lubrication equipment is used to fill
a transaxle, be sure the equipment is properly cali-
brated. Equipment out of calibration can lead to an
underfill condition.
CLUTCH PROBLEMS
Worn, damaged, or misaligned clutch components
can cause difficult shifting, gear clash, and noise.
A worn or damaged clutch disc, pressure plate, or
release bearing can cause hard shifting and gear
clash.
REMOVAL
REMOVAL - 2.4L GAS
(1) Raise hood.
(2) Disconnect gearshift cables from shift levers/
cover assembly (Fig. 10).
(3) Remove gearshift cable retaining clips from
mounting bracket (Fig. 10). Remove cables and
secure out of way.
(4) Remove three (3) right engine mount bracket-
to-transaxle bolts (Fig. 11).
(5) Raise vehicle on hoist.
(6) Remove front wheel/tires and halfshafts.
(7) Drain transaxle fluid into suitable container.
(8) Remove front harness retainer and secure har-
ness out of way.
Fig. 10 Gearshift Cables at Transaxle
1 - SELECTOR CABLE
2 - CABLE RETAINER
3 - CABLE RETAINER
4 - CROSSOVER CABLE
5 - MOUNT BRACKET
21 - 318 T850 MANUAL TRANSAXLERS
T850 MANUAL TRANSAXLE (Continued)
ProCarManuals.com
NOTE: A new snap ring must be used to secure the
clutch pulley to the compressor. The bevel side of
the snap ring must face outward.
(5) Using snap ring pliers (Special Tool C-4574 or
equivalent), install the external snap ring (bevel side
facing outward) that secures the clutch pulley to the
front cover of the compressor. Be certain that the
snap ring is fully and properly seated in the groove.
(6) If the original clutch plate and clutch pulley
are to be reused, reinstall the original shim(s) on the
compressor shaft against the shoulder. If a new
clutch plate and/or clutch pulley are being used,
install a trial stack of shims 1.0 mm (0.040 in.) thick
on the compressor shaft against the shoulder.
(7) Install the clutch plate onto the compressor
shaft.
(8) Install and tighten the compressor shaft nut. If
necessary, a band-type oil filter wrench or a strap
wrench can be placed around the clutch plate to aid
in bolt tightening. Tighten the bolt to 17.5 N´m (155
in. lbs.).
(9) If a new clutch plate and/or clutch pulley are
being installed, the air gap between the clutch plate
and clutch pulley must be checked. (Refer to 24 -
HEATING & AIR CONDITIONING/CONTROLS -
FRONT/COMPRESSOR CLUTCH - STANDARD
PROCEDURE - COMPRESSOR CLUTCH AIR GAP).
(10) On models with the 2.4L engine only, loosely
install the four screws that secure the compressor tothe mounting bracket on the engine. Tighten the
screws to 28 N´m (21 ft. lbs.).
(11) On models with the 3.3L and 3.8L engines
only, loosely install the three screws and one nut that
secure the compressor to the engine. Tighten each of
the fasteners using the following sequence to 54 N´m
(40 ft. lbs.).
²The upper screw at the rear of the compressor.
²The lower screw at the rear of the compressor.
²The lower screw at the front of the compressor.
²The upper nut at the front of the compressor.
(12) On models with the 3.3L and 3.8L engines
only, engage the retainer on the engine wire harness
compressor clutch coil take out with the bracket on
the top of the compressor.
(13) Reconnect the engine wire harness connector
for the compressor clutch coil to the coil pigtail wire
connector on the top of the compressor.
(14) Reinstall the serpentine accessory drive belt
onto the front of the engine. (Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS - 2.4L -
INSTALLATION) or (Refer to 7 - COOLING/ACCES-
SORY DRIVE/DRIVE BELTS - 3.3L/3.8L - INSTAL-
LATION).
(15) Lower the vehicle.
(16) Reconnect the battery negative cable.
(17) If a new clutch plate and/or clutch pulley are
being installed, the new clutch components must be
burnished. (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - FRONT/COMPRESSOR
CLUTCH - STANDARD PROCEDURE - COMPRES-
SOR CLUTCH BREAK-IN).
COMPRESSOR CLUTCH COIL
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH COIL
The air conditioning compressor clutch coil electri-
cal circuit is controlled by the Powertrain Control
Module (PCM) through the compressor clutch relay,
which is located in the Intelligent Power Module
(IPM) in the engine compartment near the battery.
Begin testing of a suspected compressor clutch coil
problem by performing the preliminary checks.
PRELIMINARY CHECKS
(1) If the compressor clutch will not engage, verify
the refrigerant charge level. (Refer to 24 - HEATING
& AIR CONDITIONING/PLUMBING - FRONT/RE-
FRIGERANT - DIAGNOSIS AND TESTING -
REFRIGERANT CHARGE LEVEL). If the refriger-
ant charge level is OK, go to Step 2. If the refriger-
ant charge level is not OK, adjust the refrigerant
charge as required.
Fig. 16 Install Clutch Pulley
1 - PULLEY ASSEMBLY
2 - WOOD BLOCK
24 - 20 CONTROLS - FRONTRS
COMPRESSOR CLUTCH (Continued)
ProCarManuals.com
PLUMBING - FRONT
TABLE OF CONTENTS
page page
PLUMBING - FRONT
WARNING
WARNING...........................60
WARNING...........................60
WARNING - A/C PLUMBING.............60
CAUTION - A/C PLUMBING...............61
COMPRESSOR
DESCRIPTION.........................62
OPERATION...........................62
DIAGNOSIS AND TESTING - COMPRESSOR
NOISE DIAGNOSIS....................62
REMOVAL
REMOVAL - COMPRESSOR.............63
REMOVAL - COMPRESSOR MOUNTING
BRACKET - 2.4L ENGINE...............64
INSTALLATION
INSTALLATION - COMPRESSOR..........64
INSTALLATION - COMPRESSOR
MOUNTING BRACKET - 2.4L ENGINE......65
CONDENSER
DESCRIPTION.........................65
OPERATION...........................65
REMOVAL.............................65
INSTALLATION.........................66
DISCHARGE LINE
REMOVAL.............................67
INSTALLATION.........................68
EVAPORATOR
DESCRIPTION.........................68
OPERATION...........................68
REMOVAL.............................69
INSTALLATION.........................70
EXPANSION VALVE
DESCRIPTION.........................71
OPERATION...........................71
DIAGNOSIS AND TESTING - EXPANSION
VALVE ..............................71
REMOVAL.............................72
INSTALLATION.........................73
HEATER CORE
DESCRIPTION.........................73
OPERATION...........................73
REMOVAL
REMOVAL- HEATER CORE EXTENSION
TUBES.............................74
REMOVAL - HEATER CORE.............75
INSTALLATION
INSTALLATION- HEATER CORE
EXTENSION TUBES...................76
INSTALLATION - HEATER CORE..........77HEATER HOSE
REMOVAL.............................78
INSTALLATION.........................79
HEATER HOSES - DIESEL SUPPLEMENTAL
HEATER - BUX
REMOVAL.............................80
INSTALLATION.........................80
HEATER PIPES - DIESEL SUPPLEMENTAL
HEATER - BUX
REMOVAL.............................80
INSTALLATION.........................82
LIQUID LINE
REMOVAL.............................82
INSTALLATION.........................84
RECEIVER/DRIER
DESCRIPTION.........................85
OPERATION...........................85
REMOVAL.............................85
INSTALLATION.........................86
REFRIGERANT
DESCRIPTION.........................87
OPERATION...........................87
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM CHARGE LEVEL...............87
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS......................88
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM CHARGE LEVEL 2.5L DIESEL.....89
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT..........90
STANDARD PROCEDURE - REFRIGERANT
SYSTEM CHARGE.....................91
STANDARD PROCEDURE - REFRIGERANT
SYSTEM EVACUATE...................92
STANDARD PROCEDURE - REFRIGERANT
RECOVERY..........................93
REFRIGERANT OIL
DESCRIPTION.........................93
OPERATION...........................93
STANDARD PROCEDURE - REFRIGERANT
OIL LEVEL...........................93
SUCTION LINE
REMOVAL.............................94
INSTALLATION.........................95
SERVICE PORTS
REMOVAL.............................95
INSTALLATION.........................96
RSPLUMBING - FRONT24-59
ProCarManuals.com
CAUTION: All tools, including the refrigerant recy-
cling equipment, the manifold gauge set, and test
hoses should be kept clean and dry. Keep the work
area clean. Contamination of the refrigerant system
through careless work habits must be avoided. The
refrigerant system will remain chemically stable as
long as pure, moisture-free R-134a refrigerant and
refrigerant oil is used. Dirt, moisture, or air can
upset this chemical stability. Operational troubles
or serious damage can occur if foreign material is
introduced to the refrigerant system.
COMPRESSOR
DESCRIPTION
The compressor used on this vehicle can be one of
two models, depending upon the air conditioning sys-
tem in the vehicle. All vehicles use the Nippondenso
10S20 compressor. This compressor use an aluminum
swash plate, teflon coated pistons and aluminum
sleeveless cylinder walls. This compressor includes
an integral high pressure relief valve. The compres-
sor is secured low in the right front corner of the
engine compartment to a mounting bracket on the
cylinder block (2.4L engine), or directly to the cylin-
der block (3.3L and 3.8L engines) is integral to the
compressor. This compressor cannot be repaired. If
faulty or damaged, the entire compressor must be
replaced. The compressor clutch, pulley, and clutch
coil are available for service replacement.
OPERATION
The compressor is driven by the engine through an
electric clutch, drive pulley and belt arrangement.
The compressor is lubricated by refrigerant 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 high-pressure refrigerant
vapor to the condenser through the compressor dis-
charge port. The mechanical high pressure relief
valve is designed to vent refrigerant from the system
to protect against damage to the compressor or other
system components, caused by condenser air flow
restrictions or an overcharge of refrigerant. The valve
only vents enough refrigerant to reduce the system
pressure, then re-seats itself. The valve opens at a
discharge pressure of 3445 to 4135 kPA (500 to 600
psi) or above, and closes when a minimum discharge
pressure of 2756 kPa (400 psi) is reached.
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.
²Start the vehicle and run at idle.
²Turn the air conditioner On and listen for belt
squeal.
²If 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.
24 - 62 PLUMBING - FRONTRS
PLUMBING - FRONT (Continued)
ProCarManuals.com
(17) Remove the compressor from the engine com-
partment.
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).
REMOVAL - COMPRESSOR MOUNTING
BRACKET - 2.4L ENGINE
(1) Remove the compressor from the mounting
bracket. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/COMPRESSOR - REMOVAL).
(2) Remove the four screws that secure the com-
pressor mounting bracket to the engine (Fig. 3).
(3) Remove the compressor mounting bracket from
the engine.
INSTALLATION
INSTALLATION - COMPRESSOR
NOTE: If a replacement 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.(1) Position the compressor into the engine com-
partment.
(2) On models with the 2.4L engine, loosely install
the four screws that secure the compressor to the
mounting bracket on the engine. Tighten the screws
to 28 N´m (21 ft. lbs.).
(3) On models with the 3.3L and 3.8L engines,
loosely install the three screws and one nut that
secure the compressor to the engine. Tighten each of
the fasteners using the following sequence to 54 N´m
(40 ft. lbs.).
²The upper screw at the rear of the compressor.
²The lower screw at the rear of the compressor.
²The lower screw at the front of the compressor.
²The upper nut at the front of the compressor.
(4) On models with the 3.3L and 3.8L engines only,
engage the retainer on the engine wire harness com-
pressor clutch coil take out with the bracket on the
top of the compressor.
(5) Reconnect the engine wire harness connector
for the compressor clutch coil to the coil pigtail wire
connector on the top of the compressor.
(6) Reinstall the serpentine accessory drive belt
onto the front of the engine. (Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS - 2.4L -
INSTALLATION) or (Refer to 7 - COOLING/ACCES-
SORY DRIVE/DRIVE BELTS - 3.3L/3.8L - INSTAL-
LATION).
(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) Reconnect the discharge line fitting to the
compressor discharge port.
(11) Install and tighten 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) Reconnect the suction line fitting to the com-
pressor suction port.
(15) Install and tighten 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 -
Fig. 3 Compressor Mounting Bracket - 2.4L Engine
1 - MOUNTING BRACKET
2 - SCREWS (4)
3 - ENGINE
24 - 64 PLUMBING - FRONTRS
COMPRESSOR (Continued)
ProCarManuals.com
lower half of the door. Tighten the screws to 2 N´m
(18 in. lbs.).
(6) Position the upper intake air housing onto the
top of the evaporator housing over the recirculation
air door and the blower wheel housing. Be certain
that the upper pivot of the recirculation air door is
captured in the pivot receptacle of the upper intake
air housing.
(7) Install and tighten the three screws that secure
the upper intake air housing to the top of the out-
board end of the evaporator housing. Be certain not
to miss the screw located just inside the inboard side
of the fresh air intake opening. Tighten the screws to
2 N´m (18 in. lbs.).
(8) Install and tighten the two screws that secure
the upper intake air housing to the lower intake air
housing. Tighten the screws to 2 N´m (18 in. lbs.).
(9) Engage the two hook formations on the bottom
of the distribution housing in the two receptacles on
the evaporator housing.
(10) Roll the top of the distribution housing up
into position against the evaporator housing.
(11) Install and tighten the three screws from the
dash panel side of the unit that secure the top of the
distribution housing to the inboard end of the evapo-
rator housing. Tighten the screws to 2 N´m (18 in.
lbs.).
(12) Engage the HVAC wire harness in the routing
clips molded into the outside of the HVAC housing
components.
(13) Reconnect the HVAC wire harness connector
for the blower motor with the motor connector recep-
tacle on the bottom of the outboard end of the evap-
orator housing.
(14) Reinstall the expansion valve onto the evapo-
rator inlet and outlet tube fittings. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/EXPANSION VALVE - INSTALLATION).
(15) Install a new foam seal onto the HVAC hous-
ing seal flange around the fresh air inlet opening and
the expansion valve/evaporator tube opening on the
dash panel side of the unit.
(16) Reinstall the heater core tubes into the heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/HEATER CORE -
INSTALLATION - HEATER CORE TUBES).
(17) Reinstall the HVAC unit housing into the
vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - FRONT/HVAC HOUS-
ING - INSTALLATION).
(18) Run the HVAC Control Actuator Calibration
procedure(Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING)(Refer to 24
- HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING).EXPANSION VALVE
DESCRIPTION
The front ªHº valve-type thermal expansion valve
(TXV) is located at the dash panel between the liquid
and suction lines, and the evaporator coil. The
assembly consists of an H-valve body and a thermal
sensor. High-pressure, low temperature liquid refrig-
erant from the liquid line passes through the expan-
sion valve orifice, converting it into a low-pressure,
low-temperature mixture of liquid and gas before it
enters the evaporator coil. The expansion valve is a
factory calibrated unit and cannot be adjusted or
repaired. If faulty or damaged, the expansion valve
must be replaced.
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 thermo sensor
measures refrigerant suction gas temperature which
is monitored by the a/c control assembly.
DIAGNOSIS AND TESTING - EXPANSION VALVE
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
NOTE: The expansion valve should only be tested
following testing of the compressor.
NOTE: Liquid CO is required to test the expansion
valve. This material is available from most welding
supply facilities. Liquid CO is 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.
RSPLUMBING - FRONT24-71
EVAPORATOR (Continued)
ProCarManuals.com
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.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM CHARGE LEVEL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
NOTE: The proper amount of R-134a refrigerant for
the refrigerant system in this model is:
²Single or Dual Zone (Front Unit Only) - 0.96
kilograms (2.13 pounds or 34 ounces)
²Three Zone (Front and Rear Units) - 1.31 kilo-
grams (2.88 pounds or 46 ounces)The procedure that follows should be used to deter-
mine whether the refrigerant system contains the
proper refrigerant charge. Symptoms of an improper
refrigerant charge (low) include: poor air conditioner
performance, fog emitted from the air conditioner
outlets, a hissing sound from the expansion valve/
evaporator area. There are two different methods
with which the refrigerant charge level may be
tested:
²Using a DRBIIItscan tool, a thermocouple and
the Charge Determination Chart (Fig. 33). Refer to
the appropriate diagnostic information.
²Using a manifold gauge set, a thermocouple and
the Charge Determination Chart (Fig. 33).
A temperature probe is required to measure liquid
line temperature. The clamp-on, Type K thermocou-
ple temperature probe used in this procedure is
available through the DaimlerChrysler Professional
Service Equipment (PSE) program. This probe (PSE
#66-324-0014 or #80PK-1A) is compatible with tem-
perature-measuring instruments that accept Type K
thermocouples, and have a miniature connector
input. Other temperature probes are available
through aftermarket sources; however, all references
in this procedure will reflect the use of the probe
made available through the PSE program.
In order to use the temperature probe, a digital
thermometer will also be required. If a digital ther-
mometer is not available, an adapter is available
through the PSE program that will convert any stan-
dard digital multimeter into a digital thermometer.
This adapter is designed to accept any standard Type
K thermocouple. If a digital multimeter is not avail-
able, this tool is also available through the PSE pro-
gram.
NOTE: When connecting the service equipment
couplings to the refrigerant system service ports,
be certain that the valve of each coupling is fully
closed. This will reduce the amount of effort
required to make the connection.
(1) Remove the caps from the refrigerant system
service ports and attach a manifold gauge set or a
R-134a refrigerant recovery/recycling/charging sta-
tion that meets SAE Standard J2210 to the refriger-
ant system.
(2) Attach a clamp-on thermocouple to the liquid
line. The thermocouple must be placed as close to the
A/C pressure transducer as possible to accurately
observe liquid line temperature.
(3) Bring the refrigerant system up to operating
temperature and pressure. This is done by allowing
the engine to run at idle under the following condi-
tions for five minutes.
(a) Front windows are open.
(b) Transaxle in Park.
RSPLUMBING - FRONT24-87
ProCarManuals.com
(c) Front heater-A/C controls set to outside air,
full cool, panel mode, blower high, and compressor
engaged.
(d) If the vehicle is so equipped, the rear heater-
A/C controls must be set to full cool and blower
high.
(4) Raise the liquid line (discharge) pressure to
about 1793 kPa (260 psi) by placing a piece of card-
board over part of the front side of the condenser. To
place the cardboard properly, remove the upper radi-
ator sight shield from the front fascia. Cover only
enough of the condenser to raise and maintain the
liquid line pressure at the specified level.
(5) Observe the liquid line (discharge) pressure
and liquid line temperature. Using the Charge Deter-
mination Chart (Fig. 33), determine whether the
refrigerant system is operating within the Proper
Charge Range.
(a) If the refrigerant system is operating in the
Undercharged area of the chart, add 0.057 kilo-
gram (0.125 pound or 2 ounces) of refrigerant to
the system.
(b) If the refrigerant system is operating in the
Overcharged area of the chart, reclaim 0.057 kilo-
gram (0.125 pound or 2 ounces) of refrigerant from
the system.(6) Recheck the system charge level following each
refrigerant adjustment. Continue this process until
the system readings are in the Proper Charge Range
area on the Charge Determination Chart.
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS
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).
If the air conditioning system is not cooling prop-
erly, determine if the refrigerant system is fully-
charged. (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - FRONT/REFRIGER-
ANT - DIAGNOSIS AND TESTING - REFRIGER-
ANT SYSTEM CHARGE LEVEL).
If the refrigerant system is low or empty; a leak at
a refrigerant line, connector fitting, component, or
component seal is likely. While an oily residue on or
near refrigerant system lines, connector fittings, com-
ponents, or component seals can indicate the general
Fig. 33 Charge Determination Chart, Ambient Test Condition 85ÉF
24 - 88 PLUMBING - FRONTRS
REFRIGERANT (Continued)
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