sensor CHRYSLER VOYAGER 2003 Service Manual

TIRES
DESCRIPTION
DESCRIPTION - TIRE
Tires are designed and engineered for each specific
vehicle. They provide the best overall performance
for normal operation. The ride and handling charac-
teristics match the vehicle's requirements. With
proper care they will give excellent reliability, trac-
tion, skid resistance, and tread life.
Driving habits have more effect on tire life than
any other factor. Careful drivers will obtain, in most
cases, much greater mileage than severe use or care-
less drivers. A few of the driving habits which will
shorten the life of any tire are:
²Rapid acceleration
²Severe application of brakes
²High-speed driving
²Taking turns at excessive speeds
²Striking curbs and other obstacles
²Operating vehicle with over or under inflated
tire pressures
Radial ply tires are more prone to irregular tread
wear. It is important to follow the tire rotation inter-
val shown in the section on Tire Rotation. This will
help to achieve a greater tread-life potential.
TIRE IDENTIFICATION
Tire type, size, load index and speed rating are
encoded in the letters and numbers imprinted on the
side wall of the tire. Refer to the Tire Identification
chart to decipher the code. For example purposes, the
tire size P225/60 R 16 97 T is used in the chart. An
All Season type tire will also have eitherM+S,M&
SorM-S(indicating mud and snow traction)
imprinted on the side wall. An Extra or Light Load
marking ªXLº or ªLLº may also be listed on the side-
wall. The absence of an ªXLº or ªLLº marking infers
a standard load tire.
TIRE IDENTIFICATION
PTIRE TYPE (Not
present on all tires)P - Passenger
T - Temporary
C - Commercial
LT - Light Truck
225SECTIONAL WIDTHSHOWN IN
MILLIMETERS
60ASPECT RATIOSECTIONAL HEIGHT
÷ SECTIONAL WIDTH
(Refer to Aspect Ratio
Figure 22 )
Fig. 20 Mounting Tire Using Rotating Wheel
Machine
1 - HEAD OF CHANGER LOCATED HERE
2 - VALVE STEM
Fig. 21 Mounting Tire Using Rotating Tool Machine
1 - VALVE STEM
2 - MOUNTING END OF TOOL
3 - BEAD BREAKER (KEEP CLEAR OF SENSOR)
RSTIRES/WHEELS22-13
SENSOR - TPM (Continued)
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Care must be taken in the selection of tire and
wheel cleaning chemicals and equipment to prevent
damage to the wheels. Any of the ªDO NOT USEº
items listed below WILL damage chrome plated and
painted aluminum wheels.
DO NOT USE:
²any abrasive metal cleaner
²any abrasive cleaning pad or brush
²any cleaner that contains an acid (this will
immediately react with and discolor the chromium
surface)
²chrome polish (unless it is buffed off immedi-
ately after application)
²oven cleaner
²a car wash that uses carbide-tipped wheel clean-
ing brushes
SPECIFICATIONS
WHEEL
SPECIFICATIONS
DESCRIPTION SPECIFICATION
Wheel Mounting (Lug)
Nut Hex Size19 mm
Wheel Mounting Stud
SizeM12 x 1.5 mm
TORQUE SPECIFICATIONS
DESCRIPTION N´mFt.
Lbs.In.
Lbs.
TPM Sensor Mounting Nut 4 Ð 35
Wheel Mounting (Lug ) Nut 135 100 Ð
WHEEL COVER
DESCRIPTION
This vehicle uses a bolt-on type wheel cover (Fig.
30).
This bolt-on wheel cover cannot be removed from
the wheel until three of the five wheel mounting nuts
shown are removed (Fig. 30). The bolt-on wheel cover
can then be removed with the remaining two wheel
nuts tightened in place.
REMOVAL
(1) Noting the location of the valve stem in rela-
tionship to the wheel mounting nuts, remove the
three wheel mounting nuts securing the wheel cover
to the wheel and hub (Fig. 30).
CAUTION: When removing the wheel cover, do not
pry the wheel cover from the wheel. This can resultin damage to the wheel cover. The wheel cover is
removed by pulling it off the wheel by hand.
(2) Grasp the wheel cover at the edges in line with
the remaining installed wheel nuts and pull straight
outward from the wheel. This will pop the wheel
cover retaining tabs over the two remaining wheel
nuts, removing the wheel cover from the wheel.
INSTALLATION
NOTE: Wheel mounting nuts must be installed on
the studs as shown to allow installation of the
wheel cover (Fig. 31).
Fig. 30 Nuts Securing Wheel Cover
1 - VALVE STEM
2 - BOLT-ON WHEEL COVER
3 - NUTS SECURING WHEEL COVER
Fig. 31 Two Wheel Mounting Nuts Installed
1 - WHEEL
2 - VALVE STEM
3 - HUB PILOT
4 - NUTS
RSTIRES/WHEELS22-19
WHEELS (Continued)
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²air recirculation button. The Recirculate button
contains an LED that illuminates to show when the
function is in operation.
²an air conditioning button that allows the com-
pressor to be turned on/off. The Snowflake button
contains an LED that illuminates to shown when the
function is in operation.
²rotary knobs for front and rear fan speed selec-
tion.
²a rotary knob for mode control.
REAR CONTROL PANEL
A rear control panel centrally mounted on the
headliner has a rotary adjustment for temperature
and fan speed control of the rear unit by intermedi-
ate seat passengers when the front control rear knob
is set to the rear position.
DESCRIPTION - AUTOMATIC TEMPERATURE
CONTROL
The Automatic Temperature Control (ATC) allows
occupants to select a comfort temperature, which is
the perceived temperature level not the actual pas-
senger compartment air temperature.
The Automatic Temperature Control system
includes a dust and odor air filter. The filter element
is the same size as the air conditioning evaporator to
ensure ample capacity. A door at the base of the
heater and air conditioning housing below the glove
box provides easy access to the filter element.
The ATC computer utilizes integrated circuitry and
information carried on the Programmable Communi-
cations Interface (PCI) data bus network to monitor
many sensors and switch inputs throughout the vehi-
cle. In response to those inputs, the internal circuitry
and programming of the ATC computer allow it to
control electronic functions and features of the ATC
system. The inputs to the ATC computer are:
²Vehicle Speed/Engine RPM± The ATC com-
puter monitors engine RPM, vehicle speed and Man-
ifold Absolute Pressure information from the PCM.
²Coolant Temperature± ATC computer moni-
tors Coolant temperature received from the PCM and
converts it to degrees Fahrenheit.
²Ambient Temperature± ATC computer moni-
tors Ambient temperature from the Compass Mini
Trip Computer (CMTC) and converts it to degrees
Fahrenheit.
²Engine Miscellaneous Sensor Status±ATC
computer monitors A/C disable information from the
PCM.
²Refrigerant Pressure± ATC computer moni-
tors Barometric Pressure, Intake Air Temperature,
High Side Pressure and Methanol Content as broad-
cast by the PCM.²Door Ajar Status± The ATC computer moni-
tors Driver Front Door, Passenger Front Door, Left
Rear Door, Right Rear Door and Liftgate ajar infor-
mation, as identified by the Body Control Module
(BCM), to determine if all in-car temperatures should
be maintained.
²Dimming± The ATC computer monitors dim-
ming status from the BCM to determine the required
level of brightness and will dim accordingly.
²Vehicle Odometer± The ATC computer moni-
tors the vehicle odometer information from the BCM
to prevent flashing the VF tube icons if the manual
motor calibration or manual cool down tests have
failed. Flashing of the display icons will cease when
the vehicle odometer is greater than 3 miles.
²English/Metric± The ATC computer monitors
the English/Metric information broadcast by the
CMTC. The set temp displays for both the front and
rear control heads will be set accordingly.
²Vehicle Identification Number± The ATC
computer monitors the last eight characters of the
VIN broadcast by the PCM and compares it to the
information stored in EEPROM. If it is different, the
new number will be stored over the old one and a
motor calibration shall be initiated.
²A/C System Information± The ATC computer
will send a message for Evaporator Temperature too
Low, Fan Blower Relay status, Evaporator Sensor
Failure, Rear Window Defogger Relay and A/C Select.
FRONT CONTROL PANEL
The front control panel and integral computer is
mounted in the instrument panel.
The instrument panel mounted control and inte-
gral computer contains:
²A power button which allows the system to be
completely turned off. The display is blank when the
system is off.
²Three rocker switches that select comfort tem-
peratures from 15É to 30É C (59É to 85É F), which are
shown in the vacuum-fluorescent digital control dis-
play. If the set temp is 59 and the down button is
pressed, the set temp value will become 55 but the
display will show LO. If the set temp is 85 and the
up button is pressed, the set temp value will become
90 but the display will show HIGH. Temperatures
can be displayed in either metric or Fahrenheit,
which is controlled from the overhead console.
²A rocker switch that selects a cool-down rate.
LO-AUTO or HI-AUTO are displayed when the sys-
tem is in automatic operation.
²A defroster button which turns on the defroster
independently during full automatic control. A
defroster symbol illuminates in the display when the
button is pressed.
24 - 2 HEATING & AIR CONDITIONINGRS
HEATING & AIR CONDITIONING (Continued)
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²Air recirculation button. A Recirculation symbol
appears in the display when the button is pressed, or
when the system exceeds 80 percent circulated air
under automatic control due to high air conditioning
demand.
²Rear window defogger on/off switch. A graphic
symbol shows when the defroster is on.
²An air conditioning button that allows the com-
pressor to be turned off. A Snowflake symbol is illu-
minated when air conditioning is on, whether under
manual or automatic control.
²Rotary knob for front fan speed selection can
override the automatic controls. LEDs surrounding
the knob show the current setting.
²Rotary knob for control of the Rear system.
²A rotary knob for mode control can override the
automatic controls. LEDs surrounding the knob show
the current setting.
²Computer logic remembers the settings of the
controls when the ignition is turned off and retains
those settings after a restart. If the system is off
when the ignition is turned off it will be off when the
engine is restarted, etc.
²Computer logic provides variable air recircula-
tion under high temperature and humidity condi-
tions. Because recirculation is generally accompanied
by increased fan noise, the proportion of recirculated
to outside air gradually approaches full recirculation
over a broad temperature range.
²Computer logic enables additional heat for diesel
equipped vehicles via a supplemental diesel heater.
REAR CONTROL PANEL
A rear control panel centrally mounted on the
headliner includes a vacuum-flourescent digital dis-
play, a rocker control for temperature and rotary con-
trols for adjustment of mode and fan speed control of
the rear unit by intermediate seat passengers.
OPERATION
OPERATION - DUAL ZONE
²The mode control knob enables continously vari-
able proportioning of air flow between modes but has
detents adjacent to each icon.
²The blower control provides five separate speeds.
²When the fan is off, the HVAC computer closes
the recirculation door to prevent outside air from
entering the passenger compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes except defrost and
mix by pressing the Recirculate button on the control
panel.
²To reduce humidity for rapid defogging the A/C
compressor runs automatically in modes from ªmix'to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off, button.
OPERATION - MANUAL THREE ZONE
FRONT CONTROL PANEL
²Primary control of the rear compartment unit is
on the instrument panel. This control allows the
driver to set the rear compartment fan speed, to turn
the rear unit off, or to give control to the intermedi-
ate seat occupants by switching to the REAR posi-
tion. When the rear unit is controlled from the
instrument panel, rear air temperature is based on
the driver-side temperature control position, and the
mode (floor or overhead air) is based on the front
control's mode position.
²The mode control knob enables continously vari-
able proportioning of air flow between modes but has
detents adjacent to each icon.
²The blower control provides five separate speeds
and Off. When the fan is off, the HVAC computer
closes the recirculation door to prevent outside air
from entering the passenger compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes exccept defrost and
mix by pressing the Recirculate button on the control
panel.
²To reduce humidity for rapid defogging the A/C
compressor runs automatically in modes from ªmix'
to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off, button.
REAR CONTROL PANEL
With the rear control active, temperature selection
dictates indirectly the mode (floor or overhead air) of
the rear unit: a low temperature setting directs flow
to the overhead outlets and a high temperature set-
ting to the floor.
OPERATION - THREE ZONE ATC
Comfort temperature or perceived temperature is
affected by air flow, sun impinging on exposed skin,
etc. The air temperature may be higher or lower than
the comfort temperature. Two infrared sensors, in the
instrument panel center stack i measure the temper-
ature of the occupants to determine their comfort
level relative to the selected comfort temperature.
The HVAC computer in the control module adjusts
the air flow rate and temperature to maintain the
customer-perceived comfort temperature. The air
temperature in the passenger compartment at any
time may be slightly higher or lower than the com-
RSHEATING & AIR CONDITIONING24-3
HEATING & AIR CONDITIONING (Continued)
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diagnose the A/C system control and distribution sys-
tems. Refer to the appropriate diagnostic informa-
tion.
MANUAL TEMPERATURE CONTROL
The front blower speed and rear blower speed (if
equipped with rear HVAC) must be set to High and
the evaporator temperature sensor must be greater
than 55É F or the test will fail immediately. The test
is activated by depressing the A/C and PWR buttons
simultaneously and holding them depressed for no
less than five seconds. The PWR and A/C LEDs will
blink on and off until the test is complete. If the
LEDs stop blinking before two minutes, then the cool
down test has been completed successfully. If the two
minutes expire without the expansion valve temper-
ature reaching 20É F less than the outside air tem-
perature, then the cool down test has been failed and
further A/C system diagnosis is required. If the test
is failed, the LEDs will continue to blink until the
vehicle has been driven for greater than (8 miles).
AUTOMATIC TEMPERATURE CONTROL
The ambient air temperature in the room where
the vehicle will be tested must be a minimum of 21É
C (70ÉF) for this test. The test is activated by
depressing the A/C and PWR buttons simultaneously
and holding them depressed for no less than four sec-
onds. The snowflake icon and the DELAY text in the
ATC display will blink on and off alternately until
the test is complete. If the snowflake icon and the
DELAY text stop blinking before two minutes, then
the cool down test has been completed successfully. If
the two minutes expire without the evaporator tem-
perature reaching 20É F less than the evaporator ini-
tial temperature, then the cool down test has been
failed and further A/C system diagnosis is required.
If the test is failed, the snowflake icon and the
DELAY text will continue to blink across ignition
cycles until the vehicle has been driven for greater
than (8 miles).
DIAGNOSIS AND TESTING - A/C
PERFORMANCE TEST
An air conditioning performance test is the best
way to determine whether the system is performing
up to standard. This test also provides valuable clues
as to the possible cause of trouble with the air con-
ditioning system. The ambient air temperature in the
location where the vehicle will be tested must be a
minimum of 21É C (70ÉF) for this test.
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFOREPERFORMING 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: When connecting the service equipment
coupling to the line fitting, verify that the valve of
the coupling is fully closed. This will reduce the
amount of effort required to make the connection.
(1) Connect a tachometer to monitor the engine
speed.
(2) Remove the caps from the refrigerant system
service ports and attach a manifold gauge set to
monitor the refrigerant system pressures.
(3) Set the heater-air conditioner controls so that
the compressor is engaged, the air within the vehicle
is being recirculated, the output air is directed
through the panel outlets, the temperature control is
in the full cool position, and the blower motor is oper-
ating at its highest speed.
(4) Start the engine and allow the engine to oper-
ate for about five minutes or until it reaches normal
operating temperature. Then hold the engine speed
at 1000 rpm with the compressor clutch engaged. If
the compressor clutch does not engage, proceed with
diagnosis of the compressor clutch coil. (Refer to 24 -
HEATING & AIR CONDITIONING/CONTROLS -
FRONT/COMPRESSOR CLUTCH COIL - DIAGNO-
SIS AND TESTING).
(5) Close all the vehicle windows and doors.
(6) Insert a thermometer in the left center panel
outlet and operate the engine for five minutes.
(7) With the compressor clutch engaged, record the
left center panel outlet discharge air temperature,
the discharge pressure (high side service port), and
the suction pressure (low side service port). The com-
pressor clutch may cycle, depending upon the ambi-
ent temperature and humidity. If the clutch cycles,
use the readings obtained before the clutch disen-
gaged.
(8) Compare the discharge air temperature read-
ing to the Performance Temperature and Pressure
chart. If the temperature reading is high, check the
refrigerant system for leaks and proper refrigerant
charge level. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - FRONT/REFRIGERANT -
DIAGNOSIS AND TESTING - REFRIGERANT SYS-
TEM LEAKS) and (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - FRONT/REFRIGER-
ANT - DIAGNOSIS AND TESTING - REFRIGER-
ANT SYSTEM CHARGE LEVEL).
RSHEATING & AIR CONDITIONING24-5
HEATING & AIR CONDITIONING (Continued)
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SPECIFICATIONS - HEATER-A/C SYSTEM
ITEM DESCRIPTION NOTES
Vehicle RS - Caravan, Town & Country, Voyager
System R134a with expansion valve(s)
Compressor Nippondenso - 10S20 ND-8 PAG Oil
Freeze±up Control Evaporator temperature sensor Expansion valve mounted - input
to heater-A/C control module
Low PSI Control Pressure transducer Liquid line mounted - input to
Powertrain Control Module (PCM)
- PCM opens compressor clutch
relay < 29.4 psi
High PSI Control Pressure transducer Liquid line mounted - input to
PCM - PCM opens compressor
clutch relay > 450 psi
Pressure relief valve Compressor mounted - opens >
495 psi
Control Head Single zone, dual zone, and three zone
Manual Temperature Control (MTC) - or
Automatic Temperature Control (ATC), (Two
or Three Zone)PCI data bus messaging - ATC
uses two infrared temperature
sensors
Mode Door Electric actuator Control head driven
Blend Air Door Electric actuator
Fresh/Recirc Door Electric actuator
Blower Motor Control head switch Resistor and relay with MTC,
power module and relay with ATC
Cooling Fans Pulse width modulated variable speed PCM control through solid state
fan relay
Clutch
Clutch Control PCM PCM control through compressor
clutch relay
Clutch Coil Draw 2.2 amps @ 12V   0.5amps@ 70É F
Compressor Clutch Air Gap 0.0209- 0.0359
Diagnostics DRBIIITscan tool
RSHEATING & AIR CONDITIONING24-7
HEATING & AIR CONDITIONING (Continued)
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CONTROLS - FRONT
TABLE OF CONTENTS
page page
A/C HEATER CONTROL
STANDARD PROCEDURE - HEATER-A/C
CONTROL CALIBRATION................8
REMOVAL.............................9
INSTALLATION..........................9
A/C PRESSURE TRANSDUCER
DESCRIPTION - A/C PRESSURE
TRANSDUCER.......................10
OPERATION...........................10
DIAGNOSIS AND TESTING - A/C PRESSURE
TRANSDUCER.......................10
REMOVAL.............................10
INSTALLATION.........................11
BLEND DOOR ACTUATOR
DESCRIPTION.........................11
OPERATION...........................11
REMOVAL.............................12
INSTALLATION.........................12
BLOWER MOTOR RELAY
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING - BLOWER
MOTOR RELAY.......................14
REMOVAL.............................14
INSTALLATION.........................14
BLOWER MOTOR RESISTOR
DESCRIPTION.........................14
OPERATION...........................15
DIAGNOSIS AND TESTING - BLOWER
MOTOR RESISTOR....................15
REMOVAL.............................16
INSTALLATION.........................16
COMPRESSOR CLUTCH
DESCRIPTION.........................16
OPERATION...........................17
STANDARD PROCEDURE
STANDARD PROCEDURE - COMPRESSOR
CLUTCH AIR GAP.....................17STANDARD PROCEDURE - COMPRESSOR
CLUTCH BREAK-IN....................17
REMOVAL.............................17
INSPECTION - COMPRESSOR CLUTCH/COIL . 18
INSTALLATION.........................19
COMPRESSOR CLUTCH COIL
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH COIL........................20
COMPRESSOR CLUTCH RELAY
DESCRIPTION.........................21
OPERATION...........................21
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH RELAY......................22
REMOVAL.............................22
INSTALLATION.........................22
EVAPORATOR TEMPERATURE SENSOR
DESCRIPTION.........................22
OPERATION...........................23
REMOVAL.............................23
INSTALLATION.........................23
INFRARED TEMPERATURE SENSOR
DESCRIPTION.........................23
OPERATION...........................24
MODE DOOR ACTUATOR
DESCRIPTION.........................24
OPERATION...........................24
REMOVAL.............................25
INSTALLATION.........................25
POWER MODULE
DESCRIPTION.........................25
OPERATION...........................26
REMOVAL.............................26
INSTALLATION.........................26
RECIRCULATION DOOR ACTUATOR
DESCRIPTION.........................27
OPERATION...........................27
REMOVAL.............................27
INSTALLATION.........................28
A/C HEATER CONTROL
STANDARD PROCEDURE - HEATER-A/C
CONTROL CALIBRATION
The heater-A/C 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) Simultaneously depress and hold the Power
and Recirculation buttons on the heater-A/C control
for at least five seconds. The manual heater-A/C con-
trol power Light Emitting Diode (LED) and Recircu-
lation LED, or the Automatic Temperature Control
24 - 8 CONTROLS - FRONTRS
ProCarManuals.com

(ATC) heater-A/C control Delay and Recirculation
graphics will begin to flash when the calibration pro-
cedure has begun.
(3) The calibration procedure should take less than
two minutes to complete for the manual heater-A/C
control, and less than twenty seconds for the ATC
heater-A/C control. When the LEDs or graphics stop
flashing, the calibration procedure is complete.
(4) If the LEDs or graphics continue to flash
beyond the normal three minute (manual) or twenty
second (ATC) calibration time, it indicates that the
heater-A/C control has detected a failure and a Diag-
nostic Trouble Code (DTC) has been set. Use a
DRBIIItscan tool to perform further diagnosis. Refer
to the appropriate diagnostic information. The LEDs
or graphics will continue to flash even after the igni-
tion switch is cycled Off and On, until a successful
calibration is completed or until the vehicle has been
driven about 13 kilometers (8 miles).
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 - REMOV-
AL).
(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 heater-A/C
control (Fig. 1).
(5) Remove the six screws that secure the heater-
A/C control to the back of the instrument panel cen-
ter bezel.
(6) Remove the heater-A/C control from the instru-
ment panel center bezel.INSTALLATION
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) Position the heater-A/C control onto the back of
instrument panel center bezel.
(2) Install and tighten the six screws that secure
the heater-A/C 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 the receptacle on the back of
the heater-A/C control.
(4) Reinstall 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.
Fig. 1 Heater-A/C Control
1 - INFRARED SENSOR JUMPER CONNECTOR (ATC ONLY)
2 - INFRARED SENSOR JUMPER HARNESS (ATC ONLY)
3 - HEATER-A/C CONTROL
4 - SCREW (6)
5- INSTRUMENT PANEL CENTER BEZEL
RSCONTROLS - FRONT24-9
A/C HEATER CONTROL (Continued)
ProCarManuals.com

A/C PRESSURE TRANSDUCER
DESCRIPTION - A/C PRESSURE TRANSDUCER
The A/C pressure transducer (Fig. 2) is a switch
that is installed on a fitting located on the refriger-
ant liquid line between the filter-drier and the
expansion valve in the right rear corner of the engine
compartment. 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 take out 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 musty 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 air conditioning compressor clutch and theradiator cooling fan to help optimize air conditioning
system performance and to protect the system com-
ponents from damage. The A/C pressure transducer
input to the PCM will also prevent the air condition-
ing compressor clutch from engaging when ambient
temperatures are below about 10É C (50É F) due to
the pressure/temperature relationship of the refriger-
ant. The Schrader-type valve in the liquid line fitting
permits the A/C pressure transducer to be removed
or installed without disturbing the refrigerant in the
system. The A/C pressure transducer is diagnosed
using a DRBIIItscan tool. Refer to the appropriate
diagnostic information.
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 air conditioning system 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 compressor. Refer to the A/C Pres-
sure Transducer Voltage table for the possible condi-
tion indicated by the transducer voltage readings.
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
(1) Disconnect and isolate the battery negative
cable.
Fig. 2 A/C Pressure Transducer
1 - RIGHT FRONT STRUT TOWER
2 - CONNECTOR
3 - A/C PRESSURE TRANSDUCER
4 - RIGHT WIPER MODULE DRAIN TUBE
5 - HIGH SIDE SERVICE PORT
6 - LIQUID LINE
24 - 10 CONTROLS - FRONTRS
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damaged, the clutch electromagnetic coil unit must
be replaced.
OPERATION
The compressor clutch components provide the
means to engage and disengage the compressor from
the engine serpentine accessory drive belt. When the
clutch coil is energized, it magnetically draws the
clutch plate into contact with the clutch pulley and
drives the compressor shaft. When the coil is not
energized, the pulley freewheels on the clutch hub
bearing, which is part of the pulley.
A zener diode is connected in parallel with the
clutch electromagnetic coil. This diode controls the
dissipation of voltage induced into the coil windings
by the collapsing of the electromagnetic fields that
occurs when the compressor clutch is disengaged.
The zener diode dissipates this induced voltage by
regulating a current path to ground. This arrange-
ment serves to protect other circuits and components
from potentially damaging voltage spikes in the vehi-
cle electrical system that might occur if the voltage
induced in the clutch coil windings could not be dis-
sipated.
The compressor clutch engagement is controlled by
several components: the heater-A/C controls in the
passenger compartment, the A/C pressure transducer
on the liquid line, the evaporator temperature sensor
on the expansion valve, the Powertrain Control Mod-
ule (PCM) in the engine compartment, and the com-
pressor clutch relay in the Intelligent Power Module
(IPM). The PCM may delay compressor clutch
engagement for up to thirty seconds. (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-ULES/POWERTRAIN CONTROL MODULE -
DESCRIPTION - PCM OPERATION).
STANDARD PROCEDURE
STANDARD PROCEDURE - COMPRESSOR
CLUTCH AIR GAP
If a new clutch plate and/or clutch pulley are being
used, the air gap between the clutch plate and clutch
pulley must be checked using the following proce-
dure:
(1) Using feeler gauges, measure the air gap
between the clutch plate and the clutch pulley fric-
tion surfaces.
(2) If the air gap is not between 0.5 and 0.9 mm
(0.020 and 0.035 in.), add or subtract shims until the
desired air gap is obtained.
NOTE: The shims may compress after tightening
the compressor shaft bolt. Check the air gap in four
or more places on the clutch plate to verify that the
air gap is still correct. Spin the clutch pulley before
making the final air gap check.
STANDARD PROCEDURE - COMPRESSOR
CLUTCH BREAK-IN
After a new compressor clutch has been installed,
check that the compressor clutch coil is performing to
specifications. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS - FRONT/COMPRESSOR
CLUTCH COIL - DIAGNOSIS AND TESTING). If
the clutch coil is performing to specifications, per-
form the compressor clutch break-in procedure. This
procedure (burnishing) will seat the opposing friction
surfaces and provide a higher compressor clutch
torque capability.
(1) Set the heater-A/C controls to the A/C mode,
with the blower switch in the highest speed position.
(2) Start the engine and hold the engine speed at
1500 to 2000 rpm.
(3) Cycle the compressor clutch On and Off about
twenty times (seven seconds On, then seven seconds
Off).
REMOVAL
The refrigerant system can remain fully charged
during compressor clutch, pulley, or coil replacement.
Although the compressor assembly must be removed
from its mounting, the compressor clutch can be ser-
vice with the compressor in the vehicle.
(1) Disconnect and isolate the battery negative
cable.
(2) Raise and support the vehicle.
Fig. 11 Compressor Clutch - Typical
1 - CLUTCH PLATE
2 - SHAFT KEY (SOME MODELS)
3 - PULLEY AND BEARING
4 - CLUTCH COIL
5 - CLUTCH SHIMS
6 - SNAP RING
7 - SNAP RING
RSCONTROLS - FRONT24-17
COMPRESSOR CLUTCH (Continued)
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