1996 CHRYSLER VOYAGER clutch

pressor is driven off the back of the power steering
pump. A rubber flex coupling transfers the power from
the power steering pump to the compressor clutch.
COMPRESSOR HIGH-PRESSURE RELIEF VALVE
The High Pressure Relief Valve prevents damage
to the air conditioning system if excessive pressure
develops. Excessive pressure can be caused by con-
denser air flow blockage, refrigerant overcharge, or
air and moisture in the system.
The high pressure relief valve vents only a small
amount of refrigerant necessary to reduce system
pressure and then reseats itself. The majority of the
refrigerant is conserved in the system. The valve is
calibrated to vent at a pressure of 3450 to 4140 kPa
(500 to 600 psi). If a valve has vented a small
amount of refrigerant, it does not necessarily mean
the valve is defective.
The High Pressure Relief Valve is located on the
compressor manifold at the discharge passage.
NOTE: Special effort must be used to keep all
R-134a system components moisture-free. Moisture
in the oil is very difficult to remove and will cause a
reliability problem with the compressor.
CONDENSATE DRAIN
Condensation from the evaporator housing is
drained through the dash panel and on to the
ground. This drain must be kept open to prevent
water from collecting in the bottom of the housing.
If the drain is blocked condensate cannot drain,
causing water to back up and spill into the passenger
compartment. It is normal to see condensate drain-
age below the vehicle.
ENGINE COOLING SYSTEM REQUIREMENTS
To maintain ample temperature levels from the
heating-A/C system, the cooling system must be in
proper working order. Refer to Group 0, Lubrication
and Maintenance or Group 7, Cooling System of this
manual.
The use of a bug screen is not recommended. Any
obstructions forward of the condenser can reduce the
effectiveness of the air conditioning system.
EVAPORATOR PROBE
The Evaporator probe is located on the HVAC. The
probe prevents evaporator freeze-up by signaling the
Powertrain Control Module to cycle the compressor
ON and OFF. The probe monitors the temperature of
the refrigerant after expansion.
The evaporator probe is inserted into the evapora-
tor between the coils. The probe is a sealed unit and
cannot be adjusted or repaired. It must be replaced if
found defective.
HANDLING TUBING AND FITTINGS
Kinks in the refrigerant tubing or sharp bends in
the refrigerant hose lines will greatly reduce the
capacity of the entire system. High pressures are pro-
duced in the system when it is operating. Extreme
care must be exercised to make sure that all connec-
tions are pressure tight. Dirt and moisture can enter
the system when it is opened for repair or replace-
ment of lines or components. The refrigerant oil will
absorb moisture readily out of the air. This moisture
will convert into acids within a closed system.
CAUTION: The system must be completely empty
before opening any fitting or connection in the
refrigeration system. Open fittings with caution
even after the system has been emptied. If any
pressure is noticed as a fitting is loosened,
retighten fitting and evacuate the system again.
A good rule for the flexible hose lines is to keep
the radius of all bends at least 10 times the diame-
ter of the hose. Sharper bends will reduce the flow
of refrigerant. The flexible hose lines should be
routed so they are at least 3 inches (80 mm) from
the exhaust manifold. Inspect all flexible hose lines
to make sure they are in good condition and prop-
erly routed.
The use of correct wrenches when making con-
nections is very important. Improper wrenches or
improper use of wrenches can damage the fittings.
The internal parts of the A/C system will remain
stable as long as moisture-free refrigerant and
refrigerant oil is used. Abnormal amounts of dirt,
moisture or air can upset the chemical stability.
This may cause operational troubles or even seri-
ous damage if present in more than very small
quantities.
When opening a refrigeration system, have every-
thing you will need to repair the system ready. This
will minimize the amount of time the system must
be opened. Cap or plug all lines and fittings as
soon as they are opened. This will help prevent the
entrance of dirt and moisture. All new lines and
components should be capped or sealed until they
are ready to be used.
All tools, including the refrigerant dispensing
manifold, the manifold gauge set, and test hoses
should be kept clean and dry.
HVAC CONTROL MODULE
The HVAC control module regulates the operation
of the various actuator motors. The actuator motors
are used to move the mode, blend- air, and recirc.
doors (Fig. 2).
The control module is included in the A/C control
head located on the instrument panel. The control
head includes the blower speed switch, rear wiper
NS/GSHEATING AND AIR CONDITIONING 24 - 3
DESCRIPTION AND OPERATION (Continued)

²Set A/C to ON, if A/C Clutch does not engage
make sure Fail Codes 5 and 6 are cleared.To clear
the error code 5 and 6 the evaporator probe and/or
the wiring repair needs to be completed. Then, press
and hold the intermittent wipe button for 5 seconds.
²Run Diagnostics (Depress REAR WIPER and
REAR WASH)
²When Diagnostics is complete, Cycle to Level 4.
Display Sequence is as follows:
²REAR WIPER LED will display the Level
²INTERMITTENT LED will display ten's digit
²Short Pause
²INTERMITTENT LED will display the one's
digit.
The HVAC control module will continue to cycle
the Level and then Temperature until the level is
changed or Calibration Diagnostics and Cooldown
test is exited.
HVAC CONTROL DIAGNOSTIC CONDITIONS
For wiring circuits, wiring connectors, and Pin
numbers, refer to Group 8W, Wiring Diagrams.
After calibration, Rear Wiper LED flashing
once, Intermittent LED not flashing.
The system has passed calibration. Press the Rear
Wiper button to exit calibration.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing once. The
mode actuator did not reach defrost position.
(1) Using a voltmeter, check the mode door actua-
tor wiring connector. Check Pin 1 for battery voltage.
Move the HVAC control from the defrost to panel
position, and check Pin 6 voltage it should change
from 0.5 - 1 volts to 3.5 - 4.5 volts. If voltage is OK,
go to Step 2. If not OK, check for loose or corroded
connector, open or shorted circuit and repair as nec-
essary.
(2) Remove actuator, and check if the gear pins are
in the correct track on cam or if they are binding. If
OK, go to Step 3. If not OK, repair as necessary.
(3) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(4) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing twice. The
mode actuator did not reach panel position.
(1) Using a voltmeter, check the mode door actua-
tor wiring connector. Check Pin 1 for battery voltage.
Move the HVAC control from panel to defrost posi-
tion, and check Pin 6 voltage it should change from
3.5 - 4.5 volts to 0.5 - 1 volts. If voltage is OK, go toStep 2. If not OK, check for loose or corroded connec-
tor, open or shorted circuit and repair as necessary.
(2) Remove actuator, and check if the gear pins are
in the correct cam track or binding. If OK, go to Step
3. If not OK, repair as necessary.
(3) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(4) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing three times.
The main temperature actuator/passenger
temperature actuator on a zone system did
not reach cold stop.
(1) Check if the correct HVAC control module was
used.
(2) Using a voltmeter, check the temperature door
actuator wiring connector. Check Pin 1 for battery
voltage. Move the HVAC control from the cold to hot
position, and check Pin 5 voltage it should change
from 0.5 - 4 volts to 3.5 - 4.5 volts. If voltage is OK,
go to Step 3. If not OK, check for loose or corroded
connector, open or shorted circuit and repair as nec-
essary.
(3) Remove actuator, and check if gear pins are in
the correct cam track or binding. If OK, go to Step 4.
If not OK, repair as necessary.
(4) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(5) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing four times.
The main temperature actuator/passenger
temperature actuator on a zone system did
not reach hot stop.
(1) Check if the correct HVAC control module was
used.
(2) Using a voltmeter, check the temperature door
actuator wiring connector. Check Pin 1 for battery
voltage. Move the HVAC control from hot to cold
position and check Pin 5 voltage it should change
from 3.5 -4.5 volts 0.5 - 1.5 volts. If voltage is OK, go
to Step 3. If not OK, check for loose or corroded con-
nector, open or shorted circuit and repair as neces-
sary.
(3) Remove actuator, and check if the gear pins are
in the correct track on cam or if they are binding. If
OK, go to Step 4. If not OK, repair as necessary.
NS/GSHEATING AND AIR CONDITIONING 24 - 9
DIAGNOSIS AND TESTING (Continued)

²No charge
²Compressor not operating
Verify that the test was done with the evaporator
at room temperature. The test consists of starting
the compressor and measuring the time it takes for
the evaporator temperature to fall 7ÉC (20ÉF). If the
compressor has been running, the evaporator is cold
already and will not be capable of falling 7ÉC (20ÉF).
If the test was run with a cold evaporator, turn A/C
off and turn the blower motor switch to high position
for 3 to 5 minutes till the evaporator is to room tem-
perature. Then repeat the Calibration Diagnostic and
Cooldown test.
If refrigerant system is performing properly and
the system will not pass test. Repeat the Calibration
Diagnostic and Cooldown test to determine if the
evaporator temperature FIN sensor has developed an
open or a short circuit. If the HVAC control module
still passes Calibration test, verify Cooldown test
manually with a pocket thermometer. The outlet air
temperature must drop at least 7ÉC (20ÉF) within
two minutes. If the vehicle passes with the manual
thermometer, take HVAC control to level 4 (evapora-
tor probe temperature readout) and repeat the
Cooldown test. Ensure the evaporator is at room tem-
perature before starting test. Check if evaporator
probe will drop the temperature 7ÉC (20ÉF) in two
minutes. If the Evaporator Probe is found to be
faulty, check that the sensor is positioned in the
evaporator fins properly. If not, correct and repeat
test. If OK, replace the evaporator probe.
Once the repairs are completed, repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
A/C PERFORMANCE TEST
The air conditioning system is designed to remove
heat and humidity from the air entering the passen-
ger compartment. The evaporator, located in the
heater A/C unit, is cooled to temperatures near the
freezing point. As warm damp air passes over the
fins in the evaporator, moisture in the air condenses
to water, dehumidifying the air. Condensation on the
evaporator fins reduces the evaporators ability to
absorb heat. During periods of high heat and humid-
ity, an air conditioning system will be less effective.
With the instrument control set to RECIRC, only air
from the passenger compartment passes through the
evaporator. As the passenger compartment air dehu-
midifies, A/C performance levels rise.
PERFORMANCE TEST PROCEDURE
Review Safety Precautions and Warnings in this
group before proceeding with this procedure. Air tem-
perature in test room and on vehicle must be 21É C
(70ÉF) minimum for this test.
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 and manifold gauge set.
(2) Set control to A/C, RECIRC, and PANEL, tem-
perature lever on full cool and blower on high.
(3) Start engine and hold at 1000 rpm with A/C
clutch engaged.
(4) Engine should be warmed up with doors and
windows closed.
(5) Insert a thermometer in the left center A/C
outlet and operate the engine for five minutes. The
A/C clutch may cycle depending on ambient condi-
tions.
(6) With the A/C clutch engaged, compare the dis-
charge air temperature to the A/C Performance Tem-
peratures chart (Fig. 7).
(7) If the discharge air temperature fails to meet
the specifications in the performance temperature
chart. Refer to the Refrigerant Service Procedures for
further diagnosis.
A/C PRESSURE TRANSDUCER
The work area temperature must not be below
10ÉC (50ÉF) to test the compressor clutch circuit.
Before starting to test the transducer ensure that the
wire connector is clean of corrosion and connected
properly.
(1) With gear selector in park or neutral and park
brake set, start engine and allow to idle.
(2) Install scan tool (DRB):
²Go to main menu
²Select stand alone scan tool (DRB)
²Select refer to the proper year diagnostics
²Select climate control
²Select sensor display
²Select A/C high side volts
For A/C system to operate a voltage between .451
(Low Pressure Cutout) to 4.519 (High Pressure Cut-
out is required. Voltages outside this range indicate a
low or high pressure condition andwill notallow
the compressor to cycle.
The following chart denotes voltages and the
appropriate condition(s):
NS/GSHEATING AND AIR CONDITIONING 24 - 11
DIAGNOSIS AND TESTING (Continued)

BLOWER MOTOR AND WHEEL ASSEMBLY
VIBRATION AND/OR NOISE DIAGNOSIS
The blower speed switch, in conjunction with the
resistor block, supplies the blower motor with varied
voltage.
CAUTION: Stay clear of the blower motor and resis-
tor block (Hot). Do not operate the blower motor
with the resistor block removed from the heater A/C
housing.
Refer to the Blower Motor Vibration/Noise chart in
this section for diagnosis.
COMPRESSOR NOISE DIAGNOSIS
Excessive noise while the A/C is being used, can be
caused by loose mounts, clutch, or high operating
pressure. Verify compressor drive belt condition,
proper refrigerant charge and head pressure before
compressor repair is performed.
COMPRESSOR CLUTCH/COIL
The air conditioning compressor clutch electrical
circuit is controlled by the Powertrain Control Mod-ule. It is located in the engine compartment outboard
of the battery.
If the compressor clutch does not engage verify
refrigerant charge.
If the compressor clutch still does not engage check
for battery voltage at the pressure transducer located
on the liquid line. If voltage is not detected, refer to:
²Group 8W, Wiring diagrams.
²Powertrain Diagnostic Procedures manual for
diagnostic information.
If voltage is detected at the pressure transducer,
connect pressure transducer and check for battery
voltage between the compressor clutch connector ter-
minals.
If voltage is detected, perform A/C Clutch Coil
Tests.
TESTS
(1) Verify battery state of charge. (Test indicator in
battery should be green).
(2) Connect an ampmeter (0-10 ampere scale) in
series with the clutch coil terminal. Use a voltmeter
(0-20 volt scale) with clip leads measuring voltage
across the battery and A/C clutch.
(3) With A/C control in A/C mode and blower at
low speed, start the engine and run at normal idle.
(4) The A/C clutch should engage immediately and
the clutch voltage should be within two volts of the
battery voltage. If the A/C clutch does not engage,
test the fuse.
(5) The A/C clutch coil is acceptable if the current
draw is 2.0 to 3.7 amperes at 11.5-12.5 volts at clutch
coil. This is with the work area temperature at 21ÉC
(70ÉF). If voltage is more than 12.5 volts, add electri-
cal loads by turning on electrical accessories until
voltage reads below 12.5 volts.
Fig. 7 A/C PERFORMANCE TEMPERATURES
VOLTAGE CONDITION
0 Transducer faulty or no voltage
from PCM
.150 to .450 Transducer good/Low Pressure
Cutout condition
.451 to 4.519 Normal operating condition
4.520 to 4.850 Transducer good/High
Pressure Cutout condition
5 Transducer faulty
24 - 12 HEATING AND AIR CONDITIONINGNS/GS
DIAGNOSIS AND TESTING (Continued)

(6) If coil current reads zero, the coil is open and
should be replaced. If the ammeter reading is 4
amperes or more, the coil is shorted and should be
replaced. If the coil voltage is not within two volts of
the battery voltage, test clutch coil feed circuit for
excessive voltage drop.
EXPANSION VALVE
NOTE: Special effort must be used to keep all
R-134a system components moisture-free. Moisture
in the oil is very difficult to remove and will cause a
reliability problem with the compressor.
TESTS
NOTE: Expansion valve tests should be performed
after compressor tests.
Review Safety Precautions and Warnings in this
group. The work area and vehicle temperature must
be 21ÉC to 27ÉC (70ÉF to 85ÉF). To test the expansion
valve:
NOTE: Liquid CO2 is required to test the expansion
valve. It is available from most welding supply facil-
ities. CO2 is also available from companies which
service and sell fire extinguishers.
(1) Connect a charging station or manifold gauge
set to the refrigerant system service ports. Verify the
refrigerant charge level.
(2) Close all doors, windows and vents to the pas-
senger compartment.
(3) Set heater A/C control to A/C, full heat,
FLOOR, and high blower.
(4) Start the engine and allow to idle (1000 rpm).
After the engine has reached running temperature,
allow the passenger compartment to heat up. This
will create the need for maximum refrigerant flow
into the evaporator.
(5) I
f the refrigerant charge is sufficient, discharge
(high pressure) gauge should read 965 to 1655 kPa (140
to 240 psi). Suction (low pressure) gauge should read
140 kPa to 207 kPa (20 psi to 30 psig). If system cannot
achieve proper pressure readings, replace the expan-
sion valve. If pressure is correct, proceed with test.
WARNING: PROTECT SKIN AND EYES FROM CON-
TACTING CO2 PERSONAL INJURY CAN RESULT.
(6) If suction side low pressure is within specified
range, freeze the expansion valve control head for 30
seconds. Use a super cold substance (liquid CO2).Do
not spray R-134a Refrigerant on the expansion
valve for this test.Suction side low pressure should
drop by 10 psi. If not, replace expansion valve.(7) Allow expansion valve to thaw. The low pres-
sure gauge reading should stabilize at 140 kPa to
240 kPa (20 psi to 30 psig). If not, replace expansion
valve.
(8) When expansion valve test is complete, test
A/C overall performance. Remove all test equipment
before returning vehicle to use.
HEATER PERFORMANCE TEST
PRE-DIAGNOSTIC PREPARATIONS
Review Safety Precautions and Warnings in this
group before performing the following procedures.
Check the coolant level, drive belt tension, vacuum
line connections, radiator air flow and fan operation.
Start engine and allow to warm up to normal tem-
perature.
WARNING: DO NOT REMOVE RADIATOR CAP
WHEN ENGINE IS HOT, PERSONAL INJURY CAN
RESULT.
If vehicle has been run recently, wait 15 minutes
before removing cap. Place a rag over the cap and
turn it to the first safety stop. Allow pressure to
escape through the overflow tube. When the system
stabilizes, remove the cap completely.
MAXIMUM HEATER OUTPUT: TEST AND
ACTION
Engine coolant is provided to the heater system by
two 16 mm (5/8 inch inside diameter) heater hoses.
With engine idling at normal running temperature,
set the control to maximum heat, floor, and high
blower setting. Using a test thermometer, check the
air temperature coming from the floor outlets, refer
to Temperature Reference chart.
If the floor outlet air temperature is insufficient,
refer to Group 7, Cooling Systems for specifications.
Both heater hoses should be HOT to the touch (cool-
ant return hose should be slightly cooler than the
supply hose). If coolant return hose is much cooler
than the supply hose, locate and repair engine cool-
ant flow obstruction in heater system.
TEMPERATURE REFERENCE CHART
AMBIENT TEMP.MINIMUM FLOOR
OUTLET TEMP.
CELSIUS FAHRENHEIT CELSIUS FAHRENHEIT
15.5É 60É 62.2É 144É
21.1É 70É 63.8É 147É
26.6É 80É 65.5É 150É
32.2É 90É 67.2É 153É
24 - 14 HEATING AND AIR CONDITIONINGNS/GS
DIAGNOSIS AND TESTING (Continued)

The use of R-134a will have a positive environmen-
tal impact due to it's zero ozone depletion and low
global warming impact.
CHARGING REFRIGERANT SYSTEM
CAUTION: Do not overcharge refrigerant system,
as excessive compressor head pressure can cause
noise and system failure.
After the system has been tested for leaks and
evacuated, a refrigerant (R-134a) charge can be
injected into the system.
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 manifold gauge set.
(2) Measure refrigerant 0.96 kg (34 oz. or 2.13 lb.)
and heat to 52ÉC (125ÉF) with the charging station.
Refer to the instructions provided with the equip-
ment being used.
(3) Open the suction and discharge valves. Open
the charge valve to allow the heated refrigerant to
flow into the system. When the transfer of refriger-
ant has stopped, close the suction and discharge
valve.
(4) If all of the charge did not transfer from the
dispensing device, run engine at a high idle (1400
rpm). Set the A/C control to A/C, low blower speed,
and open windows. If the A/C compressor does not
engage, test the compressor clutch control circuit andcorrect any failure. Refer to Group 8W, Wiring Dia-
grams.
(5) Open the suction valve to allow the remaining
refrigerant to transfer to the system.
WARNING: TAKE CARE NOT TO OPEN THE DIS-
CHARGE (HIGH-PRESSURE) VALVE AT THIS TIME.
(6) Close all valves and test the A/C system perfor-
mance.
(7) Disconnect the charging station or manifold
gauge set. Install the service port caps.
EVACUATING REFRIGERANT SYSTEM
NOTE: Special effort must be used to prevent mois-
ture from entering the A/C system oil. Moisture in
the oil is very difficult to remove and will cause a
reliability problem with the compressor.
If a compressor designed to use R-134a refrigerant
is left open to the atmosphere for an extended period
of time. It is recommended that the refrigerant oil be
drained and replaced with new oil or a new compres-
sor be used. This will eliminate the possibility of con-
taminating the refrigerant system.
If the refrigerant system has been open to the
atmosphere, it must be evacuated before the system
can be filled. Moisture and air mixed with the refrig-
erant will raise the compressor head pressure above
acceptable operating levels. This will reduce the per-
formance of the air conditioner and damage the com-
pressor. Moisture will boil at near room temperature
when exposed to vacuum. To evacuate the refrigerant
system:
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 suitable charging station, refrigerant
recovery machine, or a manifold gauge set with vac-
uum pump to the service ports (Fig. 10).
(2) Open the suction and discharge valves and
start the vacuum pump. The vacuum pump should
run a minimum of 45 minutes prior to charge to
eliminate all moisture in system. When the suction
gauge reads -88 kPa (-26 in. Hg) vacuum or greater
for 45 minutes, close all valves and turn off vacuum
pump. If the system fails to reach specified vacuum,
the refrigerant system likely has a leak that must be
corrected. If the refrigerant system maintains speci-
fied vacuum for at least 30 minutes, start the vac-
uum pump, open the suction and discharge valves.
Then allow the system to evacuate an additional 10
minutes.
Fig. 9 Manifold Gauge Set- Typical
NS/GSHEATING AND AIR CONDITIONING 24 - 17
SERVICE PROCEDURES (Continued)

(3) Remove resistor block by inserting a flat blade
pry tool on the side of the resistor block and pushing
inward. Two guide lines are shown on the right hand
edge of the resistor block to help guide the blade
position. This will release the clips on the side of the
resistor block. Pull resistor block out.
INSTALLATION
For installation, reverse the above procedures.
Make sure the ªTOPº lettering is on the top of the
resistor. The coils on the Resistor Block should not be
contacting one another. Before installation, gently
separate the coils (with fingers only) if one coil is
contacting another.
BLOWER MOTOR WHEEL
The blower motor wheel is not serviced separately.
If the wheel needs to be replaced it is serviced as an
assembly of the blower motor. For service procedure
information, refer to Blower Motor Replacement in
this group.
COMPRESSOR (2.5L TURBO DIESEL)
REMOVAL
WARNING: REFER TO REFRIGERANT SERVICE
PROCEDURES FOR INFORMATION REGARDING
PROPER RECOVERY OF THE REFRIGERANT
BEFORE ATTEMPTING TO REMOVE THE COM-
PRESSOR.(1) Disconnect negative battery cable.
(2) Reclaim refrigerant.
(3) Raise vehicle on hoist.
(4) Remove refrigerant lines from compressor and
cap all lines (Fig. 10).
(5) Remove flex drive bolts from behind the power
steering pump (Fig. 20).
(6) Remove compressor mounting bolts (Fig. 20).
(7) pry compressor off of the dowel pins and
remove compressor.
INSTALLATION
(1) Transfer mounting spacer/bushings onto the
new compressor.
(2) Lift compressor into place and start compressor
mounting bolts. Do not tighten bolts at this time. The
compressor may have to be moved slightly to align
the flex drive bolts.
(3) Align compressor clutch with flex drive. Then
start both flex drive bolts. Tighten the bolts after
both flex drive bolts have been installed.
(4) Tighten compressor mounting bolts.
(5) Lower vehicle and install refrigerant lines.
Always replace O-rings and gaskets.
(6) Evacuate refrigerant system. Charge system
with the correct amount of R-134a refrigerant. The
refrigerant capacity is .91 kg.67 gm. (32 oz.62.0
oz.).
24 - 22 HEATING AND AIR CONDITIONINGNS/GS
REMOVAL AND INSTALLATION (Continued)

cranking. Whenever the Powertrain Control Module
(PCM) sets a Diagnostic Trouble Code (DTC) that
affects vehicle emissions, it illuminates the MIL. If a
problem is detected, the PCM sends a message over
the CCD Bus to the instrument cluster to illuminate
the lamp. The PCM illuminates the MIL only for
DTC's that affect vehicle emissions. The MIL stays
on continuously when the PCM has entered a
Limp-In mode or identified a failed emission compo-
nent or system. The MIL remains on until the DTC
is erased. Refer to the Diagnostic Trouble Code
charts in this group for emission related codes.
Also, the MIL either flashes or illuminates contin-
uously when the PCM detects active engine misfire.
Refer to Misfire Monitoring in this section.
Additionally, the PCM may reset (turn off) the MIL
when one of the following occur:
²PCM does not detect the malfunction for 3 con-
secutive trips (except misfire and fuel system moni-
tors).
²PCM does not detect a malfunction while per-
forming three successive engine misfire or fuel sys-
tem tests. The PCM performs these tests while the
engine is operating within6375 RPM of and within
10 % of the load of the operating condition at which
the malfunction was first detected.
STATE DISPLAY TEST MODE
The switch inputs to the Powertrain Control Mod-
ule (PCM) have two recognized states; HIGH and
LOW. For this reason, the PCM cannot recognize the
difference between a selected switch position versus
an open circuit, a short circuit, or a defective switch.
If the State Display screen shows the change from
HIGH to LOW or LOW to HIGH, assume the entire
switch circuit to the PCM functions properly. From
the state display screen, access either State Display
Inputs and Outputs or State Display Sensors.
STATE DISPLAY INPUTS AND OUTPUTS
Connect the DRB scan tool to the data link connec-
tor and access the State Display screen. Then access
Inputs and Outputs. The following list contains the
PCM system functions accessible through the Inputs
and Outputs screen.
Park/Neutral Switch
Speed Control Resume
Brake Switch
Speed Control On/Off
Speed Control Set
S/C Vent Solenoid
Actual S/C Vent Sol.
S/C Vacuum Solenoid
Actual S/C Vacuum Sol.
S/C Cancel
S/C Last Cutout
S/C Working Status
S/C Denied Status
A/C Clutch Relay
Actual A/C Clutch Relay
EGR Solenoid
Actual EGR Sol.
Automatic Shutdown Relay
Actual Automatic Shutdown Relay
Automatic Shutdown Relay Sense
Radiator Fan Control Module
Actual Radiator Fan Control Module
Duty Cycle EVAP Purge Solenoid
Actual EVAP Purge Sol.
Torque Converter Clutch Solenoid
Power Steering Switch
Closed Loop State
Current CMP Edge
Current CKP State
Current Sync State
Fuel Pump Relay
Actual Fuel Pump Relay
Ignition Sense (A21)
Malfunction Lamp
Limp-in Reason
STATE DISPLAY SENSORS
Connect the DRB scan tool to the vehicle and
access the State Display screen. Then access Sensor
Display. The following list contains the PCM system
functions accessible through the Sensor Display
screen.
Battery Temperature
Engine Coolant Temperature
Engine Coolant Temp Sensor
Throttle Position Volts
Minimum Throttle
Knock Sensor Volts
Battery Voltage
MAP Sensor Reading
Idle Air Control Motor Position
Fig. 1 Data Link (Diagnostic) Connector
25 - 2 EMISSION CONTROL SYSTEMSNS
DESCRIPTION AND OPERATION (Continued)