clutch CHRYSLER CARAVAN 2005 Service Manual

A/C COMPRESSOR CLUTCH
RELAY
DESCRIPTION
The compressor clutch relay (Fig. 7) is a Interna-
tional Standards Organization (ISO) mini-relay.
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The ISO
mini-relay terminal functions are the same as a con-
ventional ISO relay. However, the ISO mini-relay ter-
minal pattern (or footprint) is different, the current
capacity is lower, and the physical dimensions are
smaller than those of the conventional ISO relay. The
A/C compressor clutch relay is located in the inte-
grated power module (IPM) in the engine compart-
ment. See the fuse and relay map molded into the
inner surface of the cover of the IPM for A/C com-
pressor clutch relay identification and location.
The black, molded plastic case is the most visible
component of the A/C compressor clutch relay. Five
male spade-type terminals extend from the bottom of
the base to connect the relay to the vehicle electrical
system, and the ISO designation for each terminal is
molded into the base adjacent to each terminal. The
ISO terminal designations are as follows:
²30 (Common Feed)- This terminal is con-
nected to the movable contact point of the relay.
²85 (Coil Ground)- This terminal is connected
to the ground feed side of the relay control coil.
²86 (Coil Battery)- This terminal is connected
to the battery feed side of the relay control coil.
²87 (Normally Open)- This terminal is con-
nected to the normally open fixed contact point of the
relay.²87A (Normally Closed)- This terminal is con-
nected to the normally closed fixed contact point of
the relay.
OPERATION
The A/C compressor clutch relay is an electrome-
chanical switch that uses a low current input from
the powertrain control module (PCM) to control the
high current output to the compressor clutch electro-
magnetic coil. The movable common feed contact
point is held against the fixed normally closed con-
tact point by spring pressure. When the relay coil is
energized, an electromagnetic field is produced by the
coil windings. This electromagnetic field draws the
movable relay contact point away from the fixed nor-
mally closed contact point, and holds it against the
fixed normally open contact point. When the relay
coil is de-energized, spring pressure returns the mov-
able contact point back against the fixed normally
closed contact point. The resistor or diode is con-
nected in parallel with the relay coil in the relay, and
helps to dissipate voltage spikes and electromagnetic
interference that can be generated as the electromag-
netic field of the relay coil collapses.
The compressor clutch relay terminals are con-
nected to the vehicle electrical system through a
receptacle in the integrated power module (IPM). The
inputs and outputs of the A/C compressor clutch
relay include:
²The common feed terminal (30) receives a bat-
tery current input from a fuse in the IPM through a
fused B(+) circuit at all times.
²The coil ground terminal (85) receives a ground
input from the PCM through the compressor clutch
relay control circuit only when the PCM electroni-
cally pulls the control circuit to ground.
²The coil battery terminal (86) receives a battery
current input from the PCM through a fused ignition
switch output (run-start) circuit only when the igni-
tion switch is in the On or Start positions.
²The normally open terminal (87) provides a bat-
tery current output to the compressor clutch coil
through the compressor clutch relay output circuit
only when the compressor clutch relay coil is ener-
gized.
²The normally closed terminal (87A) is not con-
nected to any circuit in this application, but provides
a battery current output only when the compressor
clutch relay coil is de-energized.
The A/C compressor clutch relay cannot be
repaired and, if faulty or damaged, it must be
replaced. Refer to the appropriate wiring information
for diagnosis and testing of the micro-relay and for
complete HVAC wiring diagrams.
Fig. 7 A/C Compressor Clutch Relay
24 - 18 CONTROLS - FRONTRS

REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the cover from the integrated power
module (IPM) (Fig. 8).
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the IPM for A/C compressor
clutch relay identification and location.
(3) Remove the A/C compressor clutch relay from
the IPM.
INSTALLATION
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the integrated power module
(IPM) for A/C compressor clutch relay identification
and location.
(1) Position the A/C compressor clutch relay into
the proper receptacle in the IPM.
(2) Align the A/C compressor clutch relay termi-
nals with the terminal cavities in the IPM receptacle.
(3) Push down firmly on the A/C compressor clutch
relay until the terminals are fully seated in the ter-
minal cavities.
(4) Install the cover onto the IPM.
(5) Reconnect the negative battery cable.
A/C HEATER CONTROL
DESCRIPTION
The A/C-heater control is located at the center of
the instrument panel and uses electrical controls.
These controls provide the vehicle operator with a
number of setting options to help control the climate
and comfort within the vehicle. Refer to the owner's
manual in the vehicle glove box for more information
on the suggested operation and use of these controls.
The A/C-heater control cannot be repaired. If faulty
or damaged, the entire unit must be replaced. The
control knobs are available for service replacement.
STANDARD PROCEDURE
A/C-HEATER CONTROL CALIBRATION
The A/C-heater control module must be recali-
brated each time an actuator motor or the control
module is replaced. If the vehicle is so equipped, the
calibration procedure also includes rear HVAC posi-
tions for each actuator motor.
(1) Turn the ignition switch to the On position.
(2) If equipped with the manual temperature con-
trol (MTC) system, press and hold the Rear Wipe/
Wash and Recirculation buttoms for at least five
seconds. If equipped with the automatic temperature
control (ATC) systen, simultaneously press and hold
the Power and Recirculation buttons on the A/C-
heater control for at least five seconds. The MTC
A/C-heater control Rear Wipe/Wash Light Emitting
Diode (LED) and Recirculation LED, or the ATC A/C-
heater control Delay and Recirculation graphics will
begin to flash when the calibration procedure has
begun.
(3) The calibration procedure should take less than
two minutes to complete for the manual A/C-heater
control, and less than twenty seconds for the ATC
A/C-heater control. When the LEDs or graphics stop
flashing, the calibration procedure is complete.
(4) If the LEDs or graphics continue to flash
beyond the two minute (manual) or twenty second
(ATC) calibration time, it indicates that the A/C-
heater control has detected a failure and a Diagnostic
Trouble Code (DTC) has been set. Refer to Body
Diagnostic Procedures to perform further diagnosis.
The LEDs or graphics will continue to flash even
after the ignition switch is cycled Off and On, until a
successful calibration is completed or until the vehi-
cle has been driven about 13 kilometers (8 miles).
Fig. 8 A/C Compressor Clutch Relay
1 - INTEGRATED POWER MODULE (IPM)
2 - A/C COMPRESSOR CLUTCH RELAY
3 - FRONT CONTROL MODULE
RSCONTROLS - FRONT24-19
A/C COMPRESSOR CLUTCH RELAY (Continued)

REMOVAL
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) Disconnect and isolate the battery negative
cable.
(2) Remove the center bezel from the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL -
REMOVAL).
(3) Place the instrument panel center bezel unit
face down on a suitable work surface. Take the
proper precautions to protect the center bezel from
cosmetic damage.
(4) If the vehicle is equipped with the optional
Automatic Temperature Control (ATC) system, dis-
connect the infrared sensor jumper harness connector
from the receptacle on the back of the A/C-heater
control (Fig. 9).
(5) Remove the six screws that secure the A/C-
heater control to the back of the instrument panel
center bezel.
(6) Remove the A/C-heater control from the instru-
ment panel center bezel.
INSTALLATION
(1) Position the A/C-heater control onto the back of
instrument panel center bezel.
(2) Install the six screws that secure the A/C-
heater control to the back of the instrument panel
center bezel. Tighten the screws to 2 N´m (17 in.
lbs.).
(3) If the vehicle is equipped with the optional
ATC system, reconnect the infrared sensor jumper
harness connector to A/C-heater control.
(4) Install the center bezel onto the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - INSTAL-
LATION).
(5) Reconnect the battery negative cable.
A/C PRESSURE TRANSDUCER
DESCRIPTION
The A/C pressure transducer is a switch that is
installed on a fitting located on the refrigerant liquid
line between the receiver/drier and the expansion
valve in the right rear corner of the engine compart-
ment. An internally threaded hex fitting on the
transducer connects it to the externally threaded
Schrader-type fitting on the liquid line. A rubber
O-ring seals the connection between the transducer
and the liquid line fitting. Three terminals within a
molded plastic connector receptacle on the top of the
transducer connect it to the vehicle electrical system
through a wire lead and connector of the headlamp
and dash wire harness.
The A/C pressure transducer cannot be adjusted or
repaired and, if faulty or damaged, it must be
replaced.
OPERATION
The A/C pressure transducer monitors the pres-
sures in the high side of the refrigerant system
through its connection to a fitting on the liquid line.
The transducer will change its internal resistance in
response to the pressures it monitors. The power-
train control module (PCM) provides a five volt ref-
erence signal and a sensor ground to the transducer,
then monitors the output voltage of the transducer
on a sensor return circuit to determine refrigerant
pressure. The PCM is programmed to respond to this
and other sensor inputs by controlling the operation
of the A/C compressor clutch and the radiator cooling
fan to help optimize air conditioning system perfor-
Fig. 9 A/C-Heater Control ± ATC shown, MTC typical
1 - INFRARED SENSOR CONNECTOR (ATC ONLY)
2 - INFRARED SENSOR HARNESS (ATC ONLY)
3 - A/C-HEATER CONTROL
4 - SCREW (6)
5- INSTRUMENT PANEL CENTER BEZEL
24 - 20 CONTROLS - FRONTRS
A/C HEATER CONTROL (Continued)

mance and to protect the system components from
damage. The A/C pressure transducer input to the
PCM will also prevent the A/C compressor clutch
from engaging when ambient temperatures are below
about 4.5É C (40É F) due to the pressure/temperature
relationship of the refrigerant. The Schrader-type
valve in the liquid line fitting permits the A/C pres-
sure transducer to be removed or installed without
disturbing the refrigerant in the system. The A/C
pressure transducer is diagnosed using a DRBIIIt
scan tool. Refer to Body Diagnostic Procedures.
DIAGNOSIS AND TESTING
A/C PRESSURE TRANSDUCER
The A/C pressure transducer is tested using a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information. Before testing the A/C pressure
transducer, be certain that the transducer wire har-
ness connection is clean of corrosion and properly
connected. For the A/C to operate, an A/C pressure
transducer voltage reading between 0.451 and 4.519
volts is required. Voltages outside this range indicate
a low or high refrigerant system pressure condition
to the powertrain control module (PCM). The PCM is
programmed to respond to a low or high refrigerant
system pressure by suppressing operation of the A/C
compressor. Refer to the A/C Pressure Transducer
Voltage chart for the possible conditions indicated by
the transducer voltage reading.
A/C PRESSURE TRANSDUCER VOLTAGE
Voltage Possible Indication
0.0 1. No sensor supply voltage from
PCM.
2. Shorted sensor circuit.
3. Faulty transducer.
0.150 TO 0.450 1. Ambient temperature below
10É C (50É F).
2. Low refrigerant system
pressure.
0.451 TO 4.519 1. Normal refrigerant system
pressure.
4.520 TO 4.850 1. High refrigerant system
pressure.
5.0 1. Open sensor circuit.
2. Faulty transducer.
REMOVAL
NOTE: Note: It is not necessary to discharge the
refrigerant system to replace the A/C pressure
transducer.
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the wire harness connector from the
A/C pressure transducer (Fig. 10).
(3) Remove the A/C pressure transducer from the
fitting on the liquid line.
(4) Remove the O-ring seal from the A/C pressure
transducer fitting and discard.
INSTALLATION
NOTE: Replace the O-ring seal before installing the
A/C pressure transducer.
(1) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the A/C pressure
transducer fitting. Use only the specified O-rings as
they are made of a special material for the R-134a
system. Use only refrigerant oil of the type recom-
mended for the A/C compressor in the vehicle.
(2) Install and tighten the A/C pressure transducer
onto the fitting onto the liquid line fitting.
(3) Connect the wire harness connector to the A/C
pressure transducer.
(4) Reconnect the battery negative cable.
Fig. 10 A/C Pressure Transducer - Typical
1 - RIGHT FRONT STRUT TOWER
2 - WIRE HARNESS CONNECTOR
3 - A/C PRESSURE TRANSDUCER
4 - WIPER MODULE DRAIN TUBE
5 - HIGH SIDE SERVICE PORT
6 - LIQUID LINE
RSCONTROLS - FRONT24-21
A/C PRESSURE TRANSDUCER (Continued)

The evaporator temperature sensor cannot be
adjusted or repaired and, if faulty or damaged, it
must be replaced.
OPERATION
The evaporator temperature sensor monitors the
temperature of the conditioned air once it passes
through the A/C evaporator. The evaporator temper-
ature sensor will change its internal resistance in
response to the air temperatures it monitors and is
connected to the A/C-heater control through sensor
ground and signal circuits. As the conditioned air
temperature increases, the resistance of the evapora-
tor temperature sensor decreases and the voltage
monitored by the A/C-heater control decreases. The
external location of the evaporator temperature sen-
sor allows the sensor to be removed or installed with-
out disturbing the refrigerant in the A/C system.
The A/C-heater control uses this monitored voltage
reading as an indication of the evaporator tempera-
ture. The A/C-heater control is programmed to
respond to this input by sending electronic messages
to the powertrain control module (PCM) over the con-
troller area network (CAN) data bus. The PCM then
cycles the A/C compressor clutch as necessary to opti-
mize A/C system performance and to protect the A/C
system from evaporator freezing.
The evaporator temperature sensor cannot be
adjusted or repaired and, if faulty or damaged, it
must be replaced.
The evaporator temperature sensor is diagnosed
using the DRBIIItscan tool. Refer to Body Diagnos-
tic Procedures.
REMOVAL
RG MODELS
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the air cleaner housing from the right
side of the engine compartment.
(3) Remove the windshield wiper assembly from
the vehicle (Refer to 8 - ELECTRICAL/WIPERS/
WASHERS/WIPER MODULE - REMOVAL).
(4) Remove the temperature sensor retainer from
the expansion valve (Fig. 17).
(5) Pull the evaporator temperature sensor away
from the expansion valve far enough to access the
red release ring on the wiring connector. Push the
red ring toward the connector to release the lock and
disconnect the wire harness connector from the tem-
perature sensor.
(6) Remove the evaporator temperature sensor
from the engine compartment.
RS MODELS
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the instrument panel from the vehicle
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).
(3) Disconnect the wire harness connector from the
evaporator temperature sensor located on the top of
the HVAC housing (Fig. 18).
(4) Remove the evaporator temperature sensor
from the HVAC housing.
INSTALLATION
RG MODELS
NOTE: Any grease removed with the evaporator
temperature sensor must be replaced. Failure to do
so could result in poor A/C performance.
(1) Position the evaporator temperature sensor
into the right rear corner of the engine compartment.
(2) Reconnect the wire harness connector to the
evaporator temperature sensor.
(3) Position the evaporator temperature sensor
onto the top of the expansion valve with the sensor
probe inserted into the well in the expansion valve.
(4) Install the temperature sensor retainer.
(5) Install the window wiper module (Refer to 8 -
ELECTRICAL/WIPERS/WASHERS/WIPER MOD-
ULE - INSTALLATION).
(6) Reinstall the air cleaner housing into the right
side of the engine compartment.
(7) Reconnect the battery negative cable.
Fig. 17 Evaporator Temperature Sensor - RG Models
1 - RIGHT FRONT STRUT TOWER
2 - EVAPORATOR TEMPERATURE SENSOR
3 - EXPANSION VALVE
4 - DASH PANEL
5 - RETAINER
RSCONTROLS - FRONT24-27
EVAPORATOR TEMPERATURE SENSOR (Continued)

(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
A/C COMPRESSOR
Vehicles equipped with the 2.4L gasoline, 2.5L die-
sel, 2.8L diesel and 3.3L gasoline engines with the
front heating-A/C system only, use the Denso 10S17
A/C compressor. Vehicles equipped with the 3.3L and
the 3.8L gasoline engines with the optional rear heat-
ing-A/C system use the Denso 10S20 A/C compressor.
Both A/C compressors include an integral high pres-
sure 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, 2.8L
diesel, 3.3L gasoline and 3.8L gasoline engines.
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
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.
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.
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
A/C 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.
24 - 72 PLUMBING - FRONTRS
PLUMBING - FRONT (Continued)

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
A/C 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 SYSTEM
RECOVERY).
(2) Disconnect and isolate the negative battery
cable.
(3) Remove the nuts that secure the A/C suction
line and the A/C discharge line to the A/C compres-
sor.
(4) Disconnect the A/C suction line and the A/C
discharge line from the A/C compressor.
(5) Remove the O-ring seal and gasket from the
suction and discharge line fittings and discard.
(6) Install plugs in, or tape over the opened suc-
tion and discharge fittings and the compressor ports.
(7) Raise and support the vehicle.
(8) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(9) Disconnect the wire harness connector from the
compressor clutch coil wire connector located on the
top of the A/C compressor (Fig. 4) or (Fig. 5).
(10) On models with the 2.4L, 2.5L and 2.8L
engine, remove the four bolts that secure the A/C
compressor to the mounting bracket on the engine
(2.4L), or the cylinder block (2.5L/2.8L).
Fig. 4 A/C Compressor - 2.4L Shown, 2.5L/2.8L
Typical
1 - CLUTCH COIL WIRE CONNECTOR
2 - DISCHARGE PORT
3 - A/C COMPRESSOR
4 - SUCTION PORT
5 - BOLT (4)
6 - A/C COMPRESSOR MOUNTING BRACKET
RSPLUMBING - FRONT24-73
A/C COMPRESSOR (Continued)

(11) On models with the 3.3L and 3.8L engines,
disengage the retainer on the engine wire harness
compressor clutch coil take out from the bracket on
the top of the A/C compressor and remove the two
bolts and the two nuts that secure the A/C compres-
sor to the engine.
NOTE: If a replacement A/C 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
A/C 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 receiver/drier should always be replaced
when the A/C compressor is replaced. This will help
remove any contaminants including moisture from
the system.
(12) Remove the A/C compressor from the engine
compartment.
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. 6).(3) Remove the compressor mounting bracket from
the engine.
INSTALLATION
A/C COMPRESSOR
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 A/C compressor in the vehicle.
NOTE: The receiver/drier should always be replaced
when the A/C compressor is replaced. This help will
remove any contaminants including moisture from
the refrigerant system.
(1) Position the A/C compressor into the engine
compartment.
(2) On models with the 2.4L, 2.5L and 2.8L engine,
loosely install the four bolts that secure the A/C com-
pressor to the mounting bracket on the engine (2.4L),
or the cylinder block (2.5L/2.8L). 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 the two nuts that
secure the A/C compressor to the engine and engage
the retainer on the engine wire harness compressor
clutch coil take out to the bracket on the top of the
A/C compressor. Tighten each of the fasteners 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.
Fig. 5 A/C Compressor - 3.8L Shown, 3.3L Typical
1 - A/C COMPRESSOR
2 - BOLT (2)
3 - NUT (2)
Fig. 6 Compressor Mounting Bracket - 2.4L Engine
1 - MOUNTING BRACKET
2 - BOLTS (4)
3 - ENGINE
24 - 74 PLUMBING - FRONTRS
A/C COMPRESSOR (Continued)

²The upper bolt at the rear of the compressor.
²The lower bolt at the rear of the compressor.
(4) Connect the wire harness connector to the com-
pressor clutch coil wire connector.
(5) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(6) Lower the vehicle.
(7) Remove the tape or plugs from the suction and
discharge line fittings and the compressor ports.
(8) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them and a new gasket
onto the suction and discharge line fittings.
(9) Connect the A/C suction line and the A/C dis-
charge line to the A/C compressor.
(10) Install the nut that secures the A/C suction
line and the A/C discharge line to the A/C compres-
sor. Tighten the nuts to 23 N´m (17 ft. lbs.).
(11) Reconnect the negative battery cable.
(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).
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 located in the front of the
engine compartment behind the front fascia. The A/C
condenser is a heat exchanger that allows the high-
pressure refrigerant gas being discharged by the A/C
compressor to give up its heat to the air passing over
the condenser fins, which causes the refrigerant to
cool and change to a liquid state.The A/C condenser may be removed for service
without removing the radiator and cooling fan from
the vehicle.
The A/C condenser for vehicles equipped with the
2.4L/3.3L/3.8L engines are equipped with an integral
automatic transmission cooler and mounting provi-
sions.
OPERATION
When air passes through the fins of the A/C con-
denser, the high-pressure refrigerant gas within the
A/C condenser gives up its heat. The refrigerant then
condenses as it leaves the A/C condenser and
becomes a high-pressure liquid. The volume of air
flowing over the condenser fins is critical to the
proper cooling performance of the A/C system. There-
fore, it is important that there are no objects placed
in front of the radiator grille openings at the front of
the vehicle or foreign material on the condenser fins
that might obstruct proper air flow. Also, any factory-
installed air seals or shrouds must be properly rein-
stalled following radiator or A/C condenser service.
The A/C condenser cannot be repaired and, if
faulty or damaged, it must be replaced.
Fig. 7 A/C Condenser ± 2.4L/3.3L/3.8L Engines
1 - A/C CONDENSER
2 - AUTO TRANS COOLER TAPPING BLOCK
3 - UPPER CONDENSER MOUNTING BRACKET (2)
4 - RADIATOR
5 - LOWER CONDENSER MOUNTING BRACKET (2)
RSPLUMBING - FRONT24-75
A/C COMPRESSOR (Continued)

The following is a list of the monitored compo-
nents:
²Catalyst Monitor
²Comprehensive Components
²EGR (if equipped)
²Fuel Control (rich/lean)
²Oxygen Sensor Monitor
²Oxygen Sensor Heater Monitor
²Purge
²Misfire
²Natural Vacuum Leak Detection (NVLD)
COMPREHENSIVE COMPONENTS
Along with the major monitors, OBD II requires
that the diagnostic system monitor any component
that could affect emissions levels. In many cases,
these components were being tested under OBD I.
The OBD I requirements focused mainly on testing
emissions-related components for electrical opens and
shorts.
However, OBD II also requires that inputs from
powertrain components to the PCM be tested for
rationality, and that outputs to powertrain compo-
nents from the PCM be tested forfunctionality.
Methods for monitoring the various Comprehensive
Component monitoring include:
(1) Circuit Continuity
²Open
²Shorted high
²Shorted to ground
(2) Rationality or Proper Functioning
²Inputs tested for rationality
²Outputs tested for functionality
NOTE: Comprehensive component monitors are
continuous. Therefore, enabling conditions do not
apply. All will set a DTC and illuminate the MIL in 1-
trip.
Input RationalityÐWhile input signals to the
PCM are constantly being monitored for electrical
opens and shorts, they are also tested for rationality.
This means that the input signal is compared against
other inputs and information to see if it makes sense
under the current conditions.
PCM sensor inputs that are checked for rationality
include:
²Manifold Absolute Pressure (MAP) Sensor
²Oxygen Sensor (O2S) (slow response)
²Engine Coolant Temperature (ECT) Sensor
²Camshaft Position (CMP) Sensor
²Vehicle Speed Sensor
²Crankshaft Position (CKP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Ambient/Battery Temperature Sensors
²Power Steering Switch²Oxygen Sensor Heater
²Engine Controller
²Brake Switch
²Natural Vacuum Leak Detection (NVLD)
²P/N Switch
²Trans Controls
Output FunctionalityÐPCM outputs are tested
for functionality in addition to testing for opens and
shorts. When the PCM provides a voltage to an out-
put component, it can verify that the command was
carried out by monitoring specific input signals for
expected changes. For example, when the PCM com-
mands the Idle Air Control (IAC) Motor to a specific
position under certain operating conditions, it expects
to see a specific (target) idle speed (RPM). If it does
not, it stores a DTC.
PCM outputs monitored for functionality include:
²Fuel Injectors
²Ignition Coils
²Torque Converter Clutch Solenoid
²Idle Air Control
²Purge Solenoid
²EGR Solenoid
²Radiator Fan Control
²Trans Controls
OXYGEN SENSOR (O2S) MONITOR
DESCRIPTIONÐEffective control of exhaust
emissions is achieved by an oxygen feedback system.
The most important element of the feedback system
is the O2S. The O2S is located in the exhaust path.
Once it reaches operating temperature 300É to 350ÉC
(572É to 662ÉF), the sensor generates a voltage that
is inversely proportional to the amount of oxygen in
the exhaust. When there is a large amount of oxygen
in the exhaust caused by a lean condition, misfire or
exhaust leak, the sensor produces a low voltage,
below 450 mV. When the oxygen content is lower,
caused by a rich condition, the sensor produces a
higher voltage, above 450mV.
The information obtained by the sensor is used to
calculate the fuel injector pulse width. The PCM is
programmed to maintain the optimum air/fuel ratio.
At this mixture ratio, the catalyst works best to
remove hydrocarbons (HC), carbon monoxide (CO)
and nitrous oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the
EGR, Catalyst and Fuel Monitors, and purge.
The O2S may fail in any or all of the following
manners:
²Slow response rate (Big Slope)
²Reduced output voltage (Half Cycle)
²Heater Performance
Slow Response Rate (Big Slope)ÐResponse rate
is the time required for the sensor to switch from
lean to rich signal output once it is exposed to a
25 - 2 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)