engine CHRYSLER VOYAGER 1996 Service Manual

capacity of the system and consequently result in
higher discharge air temperatures.
NOTE: The oil used in the Denso 2.5L Turbo Diesel
and the Denso 2.0L gasoline engine compressors is
ND-8 PAG R134a refrigerant oil. Only refrigerant oil
of the same type should be used to service the sys-
tem. Do not use any other oil. The oil container
should be kept tightly capped until it is ready for
use. Tightly cap afterwards to prevent contamina-
tion from dirt and moisture. Refrigerant oil will
quickly absorb any moisture it comes in contact
with. 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 reli-
ability problem with the compressor.
It will not be necessary to check oil level in the
compressor or to add oil unless there has been an oil
loss. Oil loss at a leak point will be evident by the
presence of a wet, shiny surface around the leak.
REFRIGERANT OIL LEVEL CHECK
When an air conditioning system is first assem-
bled, all components (except the compressor) are
refrigerant oil free. After the system has been
charged with R134a refrigerant and operated, the oil
in the compressor is dispersed through the lines and
components. The evaporator, condenser, and filter-
drier will retain a significant amount of oil, refer to
the Refrigerant Oil Capacities chart. When a compo-
nent is replaced, the specified amount of refrigerant
oil must be added. When the compressor is replaced,
the amount of oil that is retained in the rest of the
system must be drained from the replacement com-
pressor. When a line or component has ruptured and
oil has escaped, the compressor should be removed
and drained. The compressor is drained through the
suction port or by removing the sump bolt on top of
the compressor, refer to Compressor Removal and
Installation procedures. The filter-drier must be
replaced along with the ruptured part. The oil capac-
ity of the system, minus the amount of oil still in the
remaining components, can be measured and poured
into the suction port of the compressor.
Example: The evaporator retains 50 ml (1.7 oz.).
The condenser retains 30 ml (1 oz) of oil, and system
capacity may be 220 ml (7.40 oz) of oil.
220 ml minus 90 ml = 130 ml (4.40 oz.).
CAUTION: The refrigerant oil used in a R-134a A/C
system is unique. Use only oils which were designed
to work with R-134a refrigerant. The oil designated
for the Denso 2.5L Turbo Diesel and Denso 2.0L gas-
oline engine compressors is ND-8 PAG compressor
oil. For gasoline vehicles still using R-12 refrigerant,
use ND8 PAG compressor oil.
SERVICING REFRIGERANT OIL LEVEL
(1) Using a refrigerant recovery machine, remove
refrigerant from the A/C system.
(2) Remove refrigerant lines from A/C compressor.
(3) Remove compressor from vehicle.
(4) From suction port on top of compressor, drain
refrigerant oil from compressor.
(5) Add system capacity minus the capacity of
components that have not been replaced through suc-
tion port on compressor. Refer to the Refrigerant Oil
Capacity Chart.
(6) Install compressor, connect refrigerant lines,
evacuate, and charge refrigerant system.
DIAGNOSIS AND TESTING
ACTUATOR CALIBRATION/DIAGNOSTICS AND
COOLDOWN TEST
GENERAL INFORMATION
If the HVAC control module is replaced, the Cali-
bration Diagnostic and Cooldown tests will need to
be performed. Once this group of tests have success-
fully passed, they can be performed individually. The
engine must be running during the test to provide
hot coolant for the heater, A/C compressor operation
and to assure that the actuators are calibrated cor-
rectly. The HVAC control module is capable of trou-
bleshooting the system in approximately 120 seconds.
If a condition is detected, an error code is displayed.
The error code cannot be erased until the condition is
repaired and the diagnostic test is performed. Check
wire before replacing components, refer to Group 8W,
Wiring Diagrams.
CAUTION: Do not remove the actuators from the
Heater-A/C unit assembly with power applied.
Removal should only be done with the Ignition OFF.
The actuators have no mechanical stops to limit the
travel. If the actuator rotates and is not connected to
the unit assembly, it will become out of calibration.
ACTUATOR CALIBRATION
Mode, Blend and Zone (if equipped) door calibra-
tion compensates for mechanical variations in the
REFRIGERANT OIL CAPACITIES
REFRIGERANT OIL CAPACITIES
COMPONENT ML OZ
Compressor 135 ml 4.5 oz
Filter-Drier 30 ml 1.0 oz
Condenser 30 ml 1.0 oz
Evaporator 50 ml 1.7 oz
NS/GSHEATING AND AIR CONDITIONING 24 - 5
DESCRIPTION AND OPERATION (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)

POSSIBLE LOCATIONS OR CAUSE OF
OBSTRUCTED COOLANT FLOW
(1) Pinched or kinked heater hoses.
(2) Improper heater hose routing.
(3) Plugged heater hoses or supply and return
ports at cooling system connections, refer to Group 7,
Cooling System.
(4) Plugged heater core.
(5) Air locked heater core.
(6) If coolant flow is verified and outlet tempera-
ture is insufficient, a mechanical problem may exist.
POSSIBLE LOCATION OR CAUSE OF
INSUFFICIENT HEAT
(1) Obstructed cowl air intake.
(2) Obstructed heater system outlets.
(3) Blend-air door not functioning properly.
TEMPERATURE CONTROL
If temperature cannot be adjusted with the TEMP
lever on the control panel, the following could require
service:
(1) Blend-air door binding.
(2) Faulty blend-air door motor.
(3) Improper engine coolant temperature.
(4) Faulty Instrument Panel Control.
SYSTEM CHARGE LEVEL TEST
The procedure below should be used to check
and/or fill the refrigerant charge in the air condition-
ing system.
NOTE: The amount of R134a refrigerant that the air
conditioning system holds is 0.96 kg (34 oz. or 2.13
lbs.).
NOTE: Low Charge, condition may be described
as:
²Loss of A/C performance
²Fog from A/C outlets
²evaporator may have a HISS sound
There are two different ways the system can be
tested:
²With a scan tool (DRB), thermocouple and the
Charge Determination Graph. Use the scan tool
(DRB) diagnostic topic: Engine±System Monitors, A/C
Pressure.
²Using a manifold gauge set, a thermocouple and
the Charge Determination Graph.
It is recommended to use the gauges or reclaim/re-
cycle equipment.
WARNING: AVOID BREATHING A/C REFRIGERANT
AND LUBRICANT VAPOR OR MIST. EXPOSURE MAY
IRRITATE EYES, NOSE AND THROAT. USE ONLY
APPROVED SERVICE EQUIPMENT MEETING SAEREQUIREMENTS TO DISCHARGE R-134a SYSTEM. IF
ACCIDENTAL SYSTEM DISCHARGE OCCURS, VEN-
TILATE WORK AREA BEFORE RESUMING SERVICE.
R-134a SERVICE EQUIPMENT OR VEHICLE A/C
SYSTEM SHOULD NOT BE PRESSURE TESTED OR
LEAK TESTED WITH COMPRESSED AIR. SOME
MIXTURES OF AIR/R-134a HAVE BEEN SHOWN TO
BE COMBUSTIBLE AT ELEVATED PRESSURES.
THESE MIXTURES ARE POTENTIALLY DANGER-
OUS AND MAY RESULT IN FIRE OR EXPLOSION
CAUSING INJURY OR PROPERTY DAMAGE.
(1) Establish your preferred method of measuring
liquid line pressure. Use a manifold gauge set or a
DRB scan tool.
(2) A
ttach a clamp-on thermocouple (Professional
Service Equipment 66-324-0014 or 80PK-1A) or equiv-
alent to the liquid line. It must be placed as close to
the A/C Pressure Transducer as possible to observe liq-
uid line temperature. Refer to ªThermocouple Probeº in
this section for more information on probe.
(3) The vehicle must be in the following modes:
²Transaxle in Park
²Engine Idling at 700 rpm
²A/C Controls Set to Outside Air
²Panel Mode
²Full Cool
²High Blower motor, (vehicle equipped with rear
A/C turn rear blower motor ON HIGH)
²A/C Button in the ON position
²Vehicle Windows Open.
²Recirc. button turned OFF
(4) Operate system for a couple of minutes to allow
the system to stabilize.
(5) Set system pressure to about 1793 kPa (260
psi) by placing a piece of cardboard over part of the
front side of the condenser. To place cardboard prop-
erly, remove the upper radiator-condenser cover.
Insert cardboard between condenser and radiator
front. This will maintain a constant pressure.
(6) Observe Liquid Line pressure and Liquid line
temperature. Using theCharge Determination
Chartdetermine where the system is currently oper-
ating. If the system is in the undercharged region,
ADD 0.057 Kg. (2 oz.) to the system and recheck
readings. If the system is in the overcharged region,
RECLAIM 0.057 Kg. (2 oz.) from the system and
recheck readings. Continue this process until the sys-
tem readings are in the proper charge area on the
Charge Determination Chart.
(7) The same procedure can be performed using
the scan tool (DRB). To determine liquid line pres-
sure, attach the scan tool, go to System Moni-
tors±A/C Pressure. Observe liquid line pressure from
A/C Pressure Transducer on digital display and digi-
tal thermometer. Refer toCharge Determination
Chartand determine where the system is operating.
NS/GSHEATING AND AIR CONDITIONING 24 - 15
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) Close all valves. Turn off and disconnect the
vacuum pump.
(4) The refrigerant system is prepared to be
charged with refrigerant.
THERMOCOUPLE PROBE
To diagnose the A/C system, a temperature probe is
required to measure liquid line temperature. The
clamp-on type K probe shown in this manual is avail-
able through the Chrysler Professional Service Equip-
ment (PSE) program. This probe is compatible with
temperature-measuring instruments that accept Type
K Thermocouples and have a miniature connector
input. Other temperature probes are available through
aftermarket sources. All references in this manual will
reflect the use of the probe made available through the
Professional Service Equipment program.
In order to use the temperature probe, a digital
thermometer will be required. If a digital thermo-meter is not available, an adapter is available
through the Professional Service Equipment pro-
gram. It can convert any standard digital multimeter
into a thermometer. This adapter is designed to
accept any standard K-type thermocouple.
If a digital multimeter is not available, it to can be
ordered through Professional Service Equipment pro-
gram.
STICKING HVAC CONTROL MODULE PUSH
BUTTONS
To service HVAC control module push buttons that
are sticking, spray between the buttons with Mopart
MP-50. The MP-50 is a all purpose lubricant for
mechanical and electrical uses. After spraying around
the push buttons wipe any excess off the radio bezel
and HVAC control module push buttons. Operate the
buttons to ensure that they are operating freely.
Fig. 10 Refrigerant Lines and Port Locations (2.5L Turbo Diesel engine)
24 - 18 HEATING AND AIR CONDITIONINGNS/GS
SERVICE PROCEDURES (Continued)

SYSTEM LEAK CHECKING
WARNING: R-134a SERVICE EQUIPMENT OR VEHI-
CLE A/C SYSTEM SHOULD NOT BE PRESSURE
TESTED OR LEAK TESTED WITH COMPRESSED
AIR. SOME MIXTURES OF AIR/R-134a HAVE BEEN
SHOWN TO BE COMBUSTIBLE AT ELEVATED
PRESSURES. THESE MIXTURES ARE POTENTIALLY
DANGEROUS AND MAY RESULT IN FIRE OR
EXPLOSION CAUSING INJURY OR PROPERTY
DAMAGE.
If the A/C system is not cooling properly, determine
if the refrigerant system is fully charged with
R-134a. This is accomplished by performing a system
Charge Level-Check or Fill. If while performing this
test A/C liquid line pressure is less than 207 kPa (30
psi) proceed to Empty Refrigerant System Leak Test.
If liquid line pressure is greater than 207 kPa (30
psi) proceed to low refrigerant level leak test. If the
refrigerant system is empty or low in refrigerant
charge, a leak at any line fitting or component seal is
likely. A review of the fittings, lines and components
for oily residue is an indication of the leak location.
To detect a leak in the refrigerant system, perform
one of the following procedures as indicated by the
symptoms.
WARNING: AVOID BREATHING A/C REFRIGERANT
AND LUBRICANT VAPOR OR MIST. EXPOSURE MAY
IRRITATE EYES, NOSE AND THROAT. USE ONLY
APPROVED SERVICE EQUIPMENT MEETING SAE
REQUIREMENTS TO DISCHARGE R-134a SYSTEM.
IF ACCIDENTAL SYSTEM DISCHARGE OCCURS,
VENTILATE WORK AREA BEFORE RESUMING SER-
VICE.
EMPTY REFRIGERANT SYSTEM LEAK TEST
(1) Evacuate the refrigerant system to the lowest
degree of vacuum possible (about 28 in Hg.). Deter-
mine if the system holds a vacuum for 15 minutes. If
vacuum is held, a leak is probably not present. If sys-
tem will not maintain vacuum level, proceed with
this procedure.
(2) Prepare a .284 Kg. (10 oz.) refrigerant charge
to be injected into the system.
(3) Connect and dispense .284 Kg. (10 oz.) of
refrigerant into the evacuated refrigerant system.
(4) Proceed to step two of Low Refrigerant Level
Leak Test.
LOW REFRIGERANT LEVEL LEAK TEST
(1) Determine if there is any (R-134a) refrigerant
in the system. Use the scan tool (DRB) under the
menu Systems Sensors±A/C Pressure test or pressuregauge liquid line temperature partial charge check.
See system charge level check or fill for procedure.
(2) Position the vehicle in a wind free work area.
This will aid in detecting small leaks.
(3) Bring the refrigerant system up to operating
temperature and pressure. This is done by allowing
the engine to run for five minutes with the system
set to the following:
²Transaxle in Park
²Engine Idling at 700 rpm
²A/C Controls Set in 100 percent outside air
²Full Panel Mode
²Blower motor ON HIGH
²A/C in the ON position
²Front Windows Open.
²Rear Air Off (If Equipped)
CAUTION: A leak detector designed for R-12 refrig-
erant will not detect leaks in a R-134a refrigerant
system.
(4) Shut off the vehicle and wait 2 to 7 minutes.
Then use an Electronic Leak Detector that is
designed to detect R-134a type refrigerant and search
for leaks. Fittings, lines, or components that appear
to be oily usually indicates a refrigerant leak. To
inspect the evaporator core for leaks, insert the leak
detector probe into the recirculating air door opening
or a heat duct.
If a thorough leak check has been completed with-
out indication of a leak, proceed to System Charge
Level-Check or Fill.
REMOVAL AND INSTALLATION
A/C PRESSURE TRANSDUCER
REMOVAL
(1) Disconnect the wire connector at the pressure
transducer.
(2) Using an open end wrench, remove the trans-
ducer from the liquid line (Fig. 11).
INSTALLATION
(1) Replace transducer O-ring.
(2) For installation, reverse the above procedures.
A/C SERVICE PORTS
WARNING: THE REFRIGERATION SYSTEM MUST
BE COMPLETELY EMPTY BEFORE PROCEEDING
WITH THIS OPERATION.
The High Side service port is serviceable, the Low
Side is not serviceable.
NS/GSHEATING AND AIR CONDITIONING 24 - 19
SERVICE PROCEDURES (Continued)

(4) Remove grommet for wiring (Fig. 16). Feed wir-
ing through blower housing (Fig. 17).
(5) Remove mounting screws for blower motor (Fig.
18).(6) Allow the blower assembly to drop down, and
remove assembly from vehicle.
INSTALLATION
For installation, reverse the above procedures.
BLOWER MOTOR RESISTOR BLOCK
REMOVAL
(1) Open hood.
(2) Locate and remove the wire connector from the
blower resistor block. Block is located at the back of
the engine compartment on the passenger side of the
vehicle under the wiper module (Fig. 19).
NOTE: It is not necessary to remove the wiper
module to access the resistor block.
WARNING: THE RESISTOR BLOCK MAY BE HOT.
DO NOT ATTEMPT TO SERVICE THE RESISTOR
BLOCK IF THE SYSTEM HAS BEEN RUNNING
RECENTLY. LET THE SYSTEM COOL DOWN
BEFORE REPAIRS ARE INITIATED.
Fig. 15 Blower Motor Cover
Fig. 16 Wiring Grommet
Fig. 17 Feeding Wiring Through Housing
Fig. 18 Blower Motor Screws
Fig. 19 Resistor Block Removal
NS/GSHEATING AND AIR CONDITIONING 24 - 21
REMOVAL AND INSTALLATION (Continued)

(2) Hand-start the stud into the expansion valve
and torque to7-11N´m(64-96in.lbs.).
(3) Carefully install the expansion valve to the
sealing plate. Install the two screws and tighten 8 to
14 N´m (70 to 130 in. lbs.) torque.
(4) Carefully install the refrigerant lines and seal-
ing plate to the expansion valve. Install the nut and
tighten 20 to 26 N´m (170 to 230 in. lbs.) torque.
(5) Install the ground wire at dash panel.
(6) Pull generator back into the proper position for
bracket mounting.
(7) Install generator field wire connector.
(8) Install the upper generator bracket.
(9) Install accessory drive belt.
(10) Evacuate and recharge system.
(11) After expansion valve is installed, the system
is charged, and leaks have checked repeat the A/C
performance check.
FILTER-DRIER ASSEMBLY
REMOVAL
WARNING: THE REFRIGERATION SYSTEM MUST
BE COMPLETELY EMPTY BEFORE PROCEEDING
WITH THIS OPERATION.
(1) Recover A/C system refrigerant.
(2) Remove liquid line at filter-drier (Fig. 21).
(3) Remove the (2) bolts holding filter-drier bracket
to radiator fan module bracket.
(4) Remove the lower liquid line at condenser.
(5) Remove the upper radiator crossmember.
(6) Pull up on radiator and slide filter-drier from
the mounting location.
INSTALLATION
(1) Before installation, replace both refrigerant
line O-rings. Then reverse the above procedures.
(2) Evacuate and recharge system.
HEATER A/C UNIT HOUSING
REMOVAL
WARNING: IF EQUIPPED WITH AIR CONDITIONING,
THE REFRIGERATION SYSTEM MUST BE COM-
PLETELY EMPTY BEFORE PROCEEDING.
(1) Set parking brake.
(2) Disconnect battery negative cable.
(3) Using a refrigerant recovery machine, remove
refrigerant from the A/C system.
(4) Remove wiper module. Refer to Group 8K,
Windshield Wipers and Washers.
(5) Drain engine coolant. Remove heater hoses at
the heater core, refer to Heater Hoses Removal and
Installation procedures. Plug coolant lines.(6) Remove suction and liquid lines at the expan-
sion valve (Fig. 27).
(7) Remove the Instrument Panel Assembly. Refer
to Group 8E, Instrument Panel and Systems.
(8) Remove heater ducts.
(9) Disconnect the two upper mounts from the
upper reinforcement and the lower mount from the
tunnel.
(10) Remove the (3) nuts (in the engine compart-
ment) securing the unit to the dash panel (Fig. 30).
(11) Disconnect the HVAC housing wiring harness.
(12) Pull the entire unit rearward until the studs
on the unit clear the dash panel. Drop the unit down.
Pull it rearward to remove it from vehicle.
INSTALLATION
(1) For installation of the assembly, reverse the
above procedures. Install new O-rings on plumbing
inlets
(2) Evacuate and recharge the A/C system.
(3) Perform HVAC control Calibration Diagnostic
and Cooldown test.
HEATER CORE
REMOVAL
(1) Drain coolant system.
(2) Remove left side lower column cover.
(3) Remove steering column assembly. Refer to
Group 19, Steering for service procedure.
(4) Remove ABS module, bracket and wiring (Fig.
31).
(5) Remove I/P to body harness interconnect and
bracket (Fig. 32).
(6) Remove lower silencer boot at base of steering
shaft (Fig. 33)
(7) Pinch off heater lines under the hood.
Fig. 30 HVAC Bolt-Up
24 - 26 HEATING AND AIR CONDITIONINGNS/GS
REMOVAL AND INSTALLATION (Continued)