REMOTE POWER STEERING FLUID RESERVOIR
REMOVE
(1) Remove the filler cap from remote power steer-
ing fluid reservoir (Fig. 31).
(2) Raise vehicle on jack stands or centered on a
frame contact type hoist. See Hoisting in the Lubri-
cation and Maintenance section of this service man-
ual, for the required lifting procedure to be used for
this vehicle.
(3) Remove at power steering pump, the power
steering fluid hose coming from the power steering
fluid reservoir. Let the power steering fluid drain out
of the reservoir and hose.
(4) Lower vehicle.
(5) Remove the fluid supply hose (Fig. 31) from the
remote power steering fluid reservoir.
(6) Remove the 2 mounting screws (Fig. 31)
attaching the remote fluid reservoir to the inner
fender.
(7) Remove remote reservoir from inner fender.
INSTALL
(1) Install remote power steering fluid reservoir on
inner fender, by first inserting tab on reservoir into
hole in inner fender. Then rotate reservoir so mount-
ing tabs are against inner fender.
(2) Install and securely tighten the 2 reservoir
mounting screws (Fig. 31).
CAUTION: The power steering fluid reservoir to
power steering pump supply hose must be routed
tightly against the strut tower and parallel to the
dash panel. It must also be routed under the wiring
harness and below the drip tube. This will prevent
the hose from coming in contact with the accessory
drive belt. The power steering fluid supply hose
must be located in its correct position by clipping it
to the stud in the strut tower (Fig. 32).(3) Install the fluid supply hose onto the power
steering fluid reservoir fitting (Fig. 31). Install the
hose clamp on the fluid supply hose at the fluid res-
ervoir.Be sure hose clamp in installed past bead
on fluid reservoir fitting.
(4) Raise vehicle on jack stands or centered on a
frame contact type hoist. See Hoisting in the Lubri-
cation and Maintenance section of this service man-
ual, for the required lifting procedure to be used for
this vehicle.
(5) Install power steering fluid supply hose on
power steering pump. Install the hose clamp on the
fluid supply hose at the power steering pump.Be
sure hose clamp in installed past bead on pump
fitting.
(6) Lower vehicle.
(7) Install routing clip for power steering fluid sup-
ply hose on stud in strut tower (Fig. 32).
(8) Fill the remote fluid reservoir to the proper
level and let the fluid settle for at least two (2) min-
utes.
(9) Start the engine and let run for a few seconds.
Then turn the engine off.
(10) Add fluid if necessary. Repeat the above pro-
cedure until the fluid level remains constant after
running the engine.
(11) Raise the front wheels off the ground.
(12) Start the engine. Slowly turn the steering
wheel right and left, lightly contacting the wheel
stops.
(13) Add power steering fluid if necessary.
(14) Lower the vehicle and turn the steering wheel
slowly from lock to lock.
(15) Stop the engine. Check the fluid level and
refill as required.
(16) If the fluid is extremely foamy, allow the vehi-
cle to stand a few minutes and repeat the above pro-
cedure.
Fig. 31 Remote Power Steering Fluid Reservoir
Fig. 32 Power Steering Fluid Hose Routing Clip
19 - 22 STEERINGNS
REMOVAL AND INSTALLATION (Continued)
CAUTION: Proper torque on the cradle plate to
suspension cradle mounting bolts is very impor-
tant.
(8) Install cradle plate on front suspension cradle
and install the 10 cradle plate to cradle attaching
bolts and nuts (Fig. 8). Tighten all attaching bolts to
a torque of 165 N´m (123 ft. lbs.).
(9) Install the bracket (Fig. 9) attaching the power
steering fluid tubes to the front suspension cradle.
CAUTION:
(10) Install the power steering fluid return hose on
the steel tube at the front suspension cradle (Fig. 4).
(11) Install a screw type hose clamp on the power
steering hose to steel tube connection.Be sure hose
clamp is installed on return tube past the upset
bead on the tube.Tighten the screw clamp to a
torque of 2 N´m (18 in. lbs.).
CAUTION: The protective heat shield sleeves must
cover the entire rubber hose and hose to tube con-
nection portion of both the power steering fluid
pressure and return hoses (Fig. 4). This is required
to prevent the power steering hoses from being
overheated.
(12) When used, properly position the protective
heat sleeves on the power steering hoses. Then, tie
strap the heat sleeves to the power steering hoses to
keep them in their proper position.
(13) Install the front tire and wheel assemblies on
vehicle. Install the wheel lug nuts and torque to 129
N´m (95 ft. lbs.).
(14) Lower the vehicle to a level were the interior
of vehicle is accessible.
(15) Using the intermediate coupler, turn the front
wheels of the vehicle to the left until the intermedi-
ate coupler shaft is properly aligned with the steer-
ing column coupler. Assemble the steering column
shaft coupler (Fig. 3) onto the steering gear interme-
diate coupler. Install steering column coupler to
intermediate shaft retaining pinch bolt (Fig. 3).
Tighten the pinch bolt nut to a torque of 28 N´m (250
in. lbs.).
CAUTION: Do not use automatic transmission fluid
in the power steering system. Only use Mopar,
Power Steering Fluid or an exact equivalent prod-
uct.
(16) Fill power steering pump fluid reservoir to the
proper level.
(17) Start the engine and let run for a few seconds.
Then turn the engine off.(18) Add fluid if necessary. Repeat the above pro-
cedure until the fluid level remains constant after
running the engine.
(19) Raise front wheels of vehicle off the ground.
(20) Start the engine. Slowly turn the steering
wheel right and left, lightly contacting the wheel
stops. Then turn the engine off.
(21) Add power steering fluid if necessary.
(22) Lower the vehicle and turn the steering wheel
slowly from lock to lock.
(23) Stop the engine. Check the fluid level and
refill as required.
(24) If the fluid is extremely foamy, allow the vehi-
cle to stand a few minutes and repeat the above pro-
cedure.
(25) Fill power steering reservoir to correct level
with Mopart, Power Steering Fluid, or equivalent.
(26) Adjust toe (Refer to Group 2 Suspension).
DISASSEMBLY AND ASSEMBLY
STEERING GEAR INNER TIE ROD BOOT
DISASSEMBLE
NOTE: The removal and installation of the inner tie
rod boot must be performed with the steering gear
assembly removed from the vehicle.
(1) Loosen the inner to outer tie rod jam nut (Fig.
15). Remove the outer tie rod from the inner tie rod.
(2) Remove nut attaching the outer tie rod end to
the steering knuckle (Fig. 16).Nut is to be
removed from tie rod end using the following
procedure, hold tie rod end stud with an 11/32
socket, while loosening and removing nut with
wrench.
Fig. 15 Inner To Outer Tie Rod Jam Nut
NSSTEERING 19 - 31
REMOVAL AND INSTALLATION (Continued)
(4) Raise the front wheels off the ground.
(5) Slowly turn the steering wheel right and left,
lightly contacting the wheel stops at least 20 times.
(6) Check the fluid level add if necessary.
(7) Lower the vehicle, start the engine and turn
the steering wheel slowly from lock to lock.
(8) Stop the engine and check the fluid level and
refill as required.
(9) If the fluid is extremely foamy or milky look-
ing, allow the vehicle to stand a few minutes and
repeat the procedure.
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
REMOVAL AND INSTALLATION
POWER STEERING PUMPÐ2.5L DIESEL
NOTE: The power steering pump is mounted below
the fuel pump on the left side of the engine. The
vehicle should be raised on a hoist to access the
pump from below.
REMOVAL
(1) Remove serpentine drive belt. Refer to Group 7,
Cooling System, for procedure.
(2) Remove power steering pump pulley. Use a hex
wrench to secure the power steering shaft while
removing the pulley bolt with a box wrench. (Fig. 2)
CAUTION: Do not use an impact wrench to remove
the pump pulley ± this can cause rear pump seal
damage. Do not secure power steering shaft with a
wrench on the coupling to the A/C compressor ±
this can cause rear pump seal damage.
(3) Remove coupling bolts (2) from A/C compressor
side of coupling.
(4) Loosen A/C compressor bolts and separate com-
pressor from bracket. Do not disconnect A/C hoses.
(5) Remove bolts (2) securing the power steering
pump to the power steering bracket.
(6) Disconnect power steering pump supply hose at
the pump and drain fluid.
(7) Disconnect power steering pressure hose at the
steering gear assembly.
(8) Remove power steering pump.
INSTALLATION
(1) Install pump on engine.
(2) Tighten pump bracket bolts to 47 N´m (35 ft.
lbs.).(3) Reverse the above procedures in steps 8
through 1 to complete installation.
(4) Add power steering fluid and perform Power
Steering Pump Initial Operation.
Fig. 2 Power Steering Pump Pulley Removal
Fig. 3 Left SIde Motor MountÐVM DIesel
19 - 2 STEERINGNS/GS
SERVICE PROCEDURES (Continued)
(13) Remove the pan and clean all sealant from
the pan and transaxle mating surfaces. Clean the
magnet and the inside of the pan.
(14) Separate the filter from the valve body to
allow additional fluid to drain from the transaxle.
Inspect the filter O-ring for any damage and replace
as necessary.
(15) After the transaxle has stopped draining,
reinstall the filter and O-ring.
(16) Apply a 1/8 inch bead of Mopar RTV Sealant
to the mounting flange of the transaxle oil pan.
Apply RTV Sealant to the underside of the attaching
bolts. Attach the oil pan to the transaxle. Tighten the
bolts to 19 N²m (165 in. lbs.).
(17) Lower the vehicle and add 4 Quarts of Mopar
ATF Plus 3 Type 7176 transaxle fluid.
(18) Start the engine and allow it to idle for a min-
imum of one minute. With the parking brake applied,
press your foot on the service brake and cycle the
transaxle from park to all gear positions ending in
neutral or park.
(19) Check the transaxle fluid level and add an
appropriate amount to bring the transaxle fluid level
to 3mm (1/8 in.) below the ADD mark on the dip-
stick.
(20) Recheck the fluid level after the transaxle is
at normal operating temperature. The level should be
in the HOT range.
FLUID DRAIN AND REFILL
(1) Raise vehicle on a hoist (See Group 0, Lubrica-
tion). Place a drain container with a large opening,
under transaxle oil pan.
(2) Loosen pan bolts and tap the pan at one corner
to break it loose allowing fluid to drain, then remove
the oil pan.
(3) Install a new filter and gasket on bottom of the
valve body and tighten retaining screws to 5 N´m (40
inch-pounds).
(4) Clean the oil pan and magnet. Reinstall pan
using new sealant. Tighten oil pan bolts to 19 N´m
(165 in. lbs.).
(5) Pour four quarts of Mopar ATF PLUS 3 (Auto-
matic Transmission Fluid) Type 7176 through the
dipstick opening.
(6) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes
applied, move selector lever momentarily to each
position, ending in the park or neutral position.
(7) Add sufficient fluid to bring level to 1/8 inch
below the ADD mark.
(8) Recheck fluid level after transaxle is at normal
operating temperature. The level should be in the
HOT region.
ALUMINUM THREAD REPAIR
Damaged or worn threads in the aluminum transaxle
case and valve body can be repaired by the use of Heli-
Coils, or equivalent. This repair consists of drilling out
the worn-out damaged threads. Then tapping the hole
with a Heli-Coil tap, or equivalent, and installing a
Heli-Coil insert, or equivalent, into the hole. This
brings the hole back to its original thread size.
Heli-Coil, or equivalent, tools and inserts are readily
available from most automotive parts suppliers.
FLUSHING COOLERS AND TUBES
When a transaxle failure has contaminated the
fluid, the oil cooler(s) must be flushed. The cooler
bypass valve in the transaxle must be replaced also.
The torque converter must also be replaced with an
exchange unit. This will ensure that metal particles
or sludged oil are not later transferred back into the
reconditioned (or replaced) transaxle.
The recommended procedure for flushing the cool-
ers and tubes is to use Tool 6906A Cooler Flusher.
WARNING: WEAR PROTECTIVE EYEWEAR THAT
MEETS THE REQUIREMENTS OF OSHA AND ANSI
Z87.1±1968. WEAR STANDARD INDUSTRIAL RUB-
BER GLOVES.
KEEP LIGHTED CIGARETTES, SPARKS, FLAMES,
AND OTHER IGNITION SOURCES AWAY FROM THE
AREA TO PREVENT THE IGNITION OF COMBUSTI-
BLE LIQUIDS AND GASES. KEEP A CLASS (B) FIRE
EXTINGUISHER IN THE AREA WHERE THE
FLUSHER WILL BE USED.
KEEP THE AREA WELL VENTILATED.
DO NOT LET FLUSHING SOLVENT COME IN CON-
TACT WITH YOUR EYES OR SKIN: IF EYE CONTAM-
INATION OCCURS, FLUSH EYES WITH WATER FOR
15 TO 20 SECONDS. REMOVE CONTAMINATED
CLOTHING AND WASH AFFECTED SKIN WITH
SOAP AND WATER. SEEK MEDICAL ATTENTION.
COOLER FLUSH USING TOOL 6906A
(1) Remove cover plate filler plug on Tool 6906A.
Fill reservoir 1/2 to 3/4 full of fresh flushing solution.
Flushing solvents are petroleum based solutions gen-
erally used to clean automatic transmission compo-
nents.DO NOTuse solvents containing acids, water,
gasoline, or any other corrosive liquids.
(2) Reinstall filler plug on Tool 6906A.
(3) Verify pump power switch is turned OFF. Con-
nect red alligator clip to positive (+) battery post.
Connect black (-) alligator clip to a good ground.
(4) Disconnect the cooler lines at the transmission.
NOTE: When flushing transmission cooler and
lines, ALWAYS reverse flush.
21 - 18 TRANSAXLE AND POWER TRANSFER UNITNS
SERVICE PROCEDURES (Continued)
WARNING: WEAR PROTECTIVE EYEWEAR THAT
MEETS THE REQUIREMENTS OF OSHA AND ANSI
Z87.1±1968. WEAR STANDARD INDUSTRIAL RUB-
BER GLOVES.
KEEP LIGHTED CIGARETTES, SPARKS, FLAMES,
AND OTHER IGNITION SOURCES AWAY FROM THE
AREA TO PREVENT THE IGNITION OF COMBUSTI-
BLE LIQUIDS AND GASES. KEEP A CLASS (B) FIRE
EXTINGUISHER IN THE AREA WHERE THE
FLUSHER WILL BE USED.
KEEP THE AREA WELL VENTILATED.
DO NOT LET FLUSHING SOLVENT COME IN CON-
TACT WITH YOUR EYES OR SKIN: IF EYE CONTAM-
INATION OCCURS, FLUSH EYES WITH WATER FOR
15 TO 20 SECONDS. REMOVE CONTAMINATED
CLOTHING AND WASH AFFECTED SKIN WITH
SOAP AND WATER. SEEK MEDICAL ATTENTION.
COOLER FLUSH USING TOOL 6906A
(1) Remove cover plate filler plug on Tool 6906A.
Fill reservoir 1/2 to 3/4 full of fresh flushing solution.
Flushing solvents are petroleum based solutions gen-
erally used to clean automatic transmission compo-
nents.DO NOTuse solvents containing acids, water,
gasoline, or any other corrosive liquids.
(2) Reinstall filler plug on Tool 6906A.
(3) Verify pump power switch is turned OFF. Con-
nect red alligator clip to positive (+) battery post.
Connect black (-) alligator clip to a good ground.
(4) Disconnect the cooler lines at the transmission.
NOTE: When flushing transmission cooler and
lines, ALWAYS reverse flush.
(5) Connect the BLUE pressure line to the OUT-
LET (From) cooler line.
(6) Connect the CLEAR return line to the INLET
(To) cooler line
(7) Turn pump ON for two to three minutes to
flush cooler(s) and lines. Monitor pressure readings
and clear return lines. Pressure readings should sta-
bilize below 20 psi. for vehicles equipped with a sin-
gle cooler and 30 psi. for vehicles equipped with dual
coolers. If flow is intermittent or exceeds these pres-
sures, replace cooler.
(8) Turn pump OFF.
(9) Disconnect CLEAR suction line from reservoir
at cover plate. Disconnect CLEAR return line at
cover plate, and place it in a drain pan.
(10) Turn pump ON for 30 seconds to purge flush-
ing solution from cooler and lines. Turn pump OFF.
(11) Place CLEAR suction line into a one quart
container of MopartATF PLUS 3 Type 7176 auto-
matic transmission fluid.
(12) Turn pump ON until all transmission fluid is
removed from the one quart container and lines. Thispurges any residual cleaning solvent from the trans-
mission cooler and lines. Turn pump OFF.
(13) Disconnect alligator clips from battery. Recon-
nect flusher lines to cover plate, and remove flushing
adapters from cooler lines.
OIL PUMP VOLUME CHECK
After the new or repaired transmission has been
installed, fill to the proper level with Mopar ATF
PLUS 3 (Type 7176) automatic transmission fluid.
The volume should be checked using the following
procedure:
(1) Disconnect theFrom coolerline at the trans-
mission and place a collecting container under the
disconnected line.
CAUTION: With the fluid set at the proper level,
fluid collection should not exceed (1) quart or inter-
nal damage to the transmission may occur.
(2) Run the engineat curb idle speed, with the
shift selector in neutral.
(3) If fluid flow is intermittent or it takes more
than 20 seconds to collect one quart of ATF, discon-
nect theTo Coolerline at the transaxle.
(4) Refill the transaxle to proper level and recheck
pump volume.
(5) If flow is found to be within acceptable limits,
replace the cooler. Then fill transmission to the
proper level, using Mopar ATF PLUS 3 (Type 7176)
automatic transmission fluid.
(6) If fluid flow is still found to be inadequate,
check the line pressure using the Transaxle Hydrau-
lic Pressure Test procedure.
(7) Check the cooler for debris on the external sur-
faces. Clean as necessary.
TRANSAXLE QUICK LEARN PROCEDURE
The quick learn procedure requires the use of the
DRBIII scan tool.
This program allows the electronic transaxle sys-
tem to recalibrate itself. This will provide the best
possible transaxle operation. The quick learn proce-
dure should be performed if any of the following pro-
cedures are performed:
²Transaxle Assembly Replacement
²Transmission Control Module Replacement
²Solenoid Pack Replacement
²Clutch Plate and/or Seal Replacement
²Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the follow-
ing conditions must be met:
²The brakes must be applied
²The engine speed must be above 500 rpm
²The throttle angle (TPS) must be less than 3
degrees
21 - 82 TRANSAXLE AND POWER TRANSFER UNITNS
SERVICE PROCEDURES (Continued)
NOTE: To avoid distortion of the drive plate, bolts
should be tightened a few turns at a time. Use a
crisscross pattern until all bolts are seated. Tighten
modular clutch plate bolts to 74 N´m (55 ft. lbs.).
NOTE: Lower control arm pinch bolts must be
installed with the bolt head rearward of the ball
joint.
(3) Fill transaxle to the proper level with the spec-
ified lubricant.
(4) While the vehicle is elevated slightly, run the
transaxle through all the forward gears. Apply
brakes and shift into reverse. Run the transaxle
through reverse gear.
(5) Check the transaxle for leaks and recheck the
level of the transaxle lubricant.
DISASSEMBLY AND ASSEMBLY
TRANSAXLE
The A-598 transaxle (Fig. 63) is similar to the
A-523, A-568 transaxle with the following exceptions.
The major differences are that the input shaft is sup-
ported by ball and roller bearings and the intermedi-
ate shaft is supported by tapered roller bearings.
Also the front intermediate bearing will not clear the
final drive gear for disassembly or reassembly.
In vehicle service is limited to:
²Shift cover components
²Sealing external joints and seals
²Service of 5th gear set and synchronizer
DISASSEMBLY
(1) Remove engine mount bracket (Fig. 64).
(2) Remove differential bearing retainer (Fig. 65).
(3) Remove extension housing (Fig. 66).
(4) Remove differential cover with soft-faced ham-
mer (Fig. 67).
Fig. 62 Modular Clutch Mounting
Fig. 61 Front Engine Mount (Right Side)
Fig. 63 A-598 Transaxle
21 - 20 A±598 MANUAL TRANSAXLENS/GS
REMOVAL AND INSTALLATION (Continued)
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) If 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
expansion 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 or R-12 Refrigerant on the
expansion valve for this test.Suction side low
pressure should drop by 10 psi. If not, replace expan-
sion 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 Table.
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.
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 REFERENCE TABLE
AMBIENT
TEMPERATUREMINIMUM FLOOR
OUTLET TEMPERATURE
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
NSHEATING AND AIR CONDITIONING 24 - 15
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)