tire pressure CHRYSLER VOYAGER 1996 Owner's Manual

(13) Remove the power steering fluid return hose
(Fig. 15) from the power steering pump.
(14) Remove the support bracket at the rear of the
power steering pump attaching the pump to the rear
of the engine (Fig. 16).
(15) Remove the 2 bolts mounting the power steer-
ing pump to the alternator/power steering pump and
belt tensioner mounting bracket (Fig. 16).
(16) Remove the power steering pump from its
mounting bracket.
(17) The power steering pump is removed from the
vehicle by pulling it out through the exhaust tunnel
area in the floor pan of the vehicle.
INSTALL
(1) Install power steering pump back in vehicle
using the reverse order of its removal through the
exhaust tunnel are of the vehicle.
(2) Install the power steering pump on its mount-
ing bracket. Install the 2 power steering pumpmounting bolts (Fig. 16). Tighten the power steering
pump mounting bolts to a torque of 54 N´m (40 ft.
lbs.).
(3) Install the support bracket attaching rear of
power steering pump to engine (Fig. 16). Tighten the
nut and bolts to a torque of 54 N´m (40 ft. lbs).
NOTE: Before connecting the power steering pres-
sure line to the power steering pump, inspect the
O-ring on the pressure line for damage and replace
if damaged.
(4) Install the power steering fluid pressure line
onto the output fitting of the power steering pump
(Fig. 15). Tighten the pressure line to pump fitting
tube nut to a torque of 31 N´m (275 in. lbs.).
(5) Install the power steering fluid low pressure
return hose on the power steering pump low pressure
fitting (Fig. 15).Be sure hose clamps are prop-
erly reinstalled and return hose is clear of all
accessory drive belts.
(6) Install the power steering fluid supply hose
from the power steering fluid reservoir, on the power
steering pump fluid fitting (Fig. 15).Be sure all
hose clamps are properly reinstalled.
(7) Install the serpentine drive belt (Fig. 11). See
Cooling, Group 7 for detailed installation procedure.
(8) Install the power steering fluid return hose on
the steel tube at the front suspension cradle (Fig.
13).
(9) Install a screw type hose clamp on the power
steering hose to steel tube connection. 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. 13). This is required
to prevent overheating of the power steering hoses.
(10) 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.
(11) Install the exhaust pipe on the exhaust man-
ifold. Install all exhaust system hangers/isolators on
the exhaust system brackets.
(12) Connect the oxygen sensor wiring harness to
the vehicle wiring harness. Install wiring harness
grommet in the floor pan of the vehicle.
(13) Install the accessory drive splash shield (Fig.
14).
(14) Lower vehicle.
CAUTION: Do not use automatic transmission fluid
in power steering system. Only use MoparT, Power
Steering Fluid, or equivalent.
Fig. 15 Power Steering Hoses At Power Steering
Pump
Fig. 16 Power Steering Pump Mounting
NSSTEERING 19 - 15
REMOVAL AND INSTALLATION (Continued)

NOTE: Before installing power steering pressure
hose on power steering pump, inspect the O-ring
on the power steering pressure hose for damage
and replace if required.
(4) Install the power steering fluid pressure line
onto the output fitting of the power steering pump
(Fig. 21). Tighten the pressure line to pump fitting
tube nut to a torque of 31 N´m (275 in. lbs.).
(5) Install the power steering fluid, low pressure
return hose on the power steering pump low pressure
fitting (Fig. 21).Be sure hose clamps are prop-
erly reinstalled.
(6) Install the power steering fluid supply hose
from the power steering fluid reservoir, on the power
steering pump fluid fitting (Fig. 21).Be sure hose is
clear of accessory drive belts and all hose
clamps are properly reinstalled.
(7) Install the serpentine drive belt (Fig. 20). See
Cooling, Group 7 for detailed installation procedure.
(8) Install the power steering fluid return hose on
the steel tube at the front suspension cradle (Fig.
18).
(9) Install a screw type hose clamp on the power
steering hose to steel tube connection.Be sure hose
clamps are properly reinstalled.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. 18). This is required
to keep the power steering hoses from becoming
overheated.
(10) When used, properly position the protective
heat sleeves on the power steering hoses (Fig. 18).
Then, tie strap the heat sleeves to the power steering
hoses to keep them in their proper position.
(11) Install the exhaust pipe on the exhaust man-
ifold. Install all exhaust system hangers/isolators on
the exhaust system brackets.
(12) Connect the oxygen sensor wiring harness to
the vehicle wiring harness. Install wiring harness
grommet in the floor pan of the vehicle.
(13) Install the accessory drive splash shield (Fig.
19).
(14) Lower vehicle.
CAUTION: Do not use automatic transmission fluid
in power steering system. Only use MoparT, Power
Steering Fluid, or equivalent.
(15) Fill the remote power steering pump fluid res-
ervoir to correct fluid level.
(16) Install cap on power steering fluid reservoir.(17) Connect the negative battery cable on the
negative battery post.
(18) Start engine and turn steering wheel several
times from stop to stop to bleed air from fluid in sys-
tem. Stop engine, check fluid level, and inspect sys-
tem for leaks. See Checking Fluid Level.
POWER STEERING FLUID RESERVOIR TO PUMP
SUPPLY HOSE
REMOVE
(1) Remove the filler cap from remote power steer-
ing fluid reservoir (Fig. 24).
(2) Using a siphon pump, remove as much power
steering fluid as possible from the power steering
fluid reservoir.
(3) Remove power steering fluid supply hose rout-
ing clip (Fig. 25) from stud in strut tower.
(4) Raise vehicle on jack stands or centered on a
frame contact type hoist. See Hoisting in the Lubri-
Fig. 24 Fluid Supply Hose At Power Steering Fluid
Reservoir
Fig. 25 Power Steering Fluid Hose Routing Clip
19 - 18 STEERINGNS
REMOVAL AND INSTALLATION (Continued)

(6) Install the power steering fluid return hose on
the steel tube at the front suspension cradle (Fig.
26).
(7) Install a screw type hose clamp on the power
steering hose to steel tube connection. Tighten the
screw clamp to a torque of 2 N´m (18 in. lbs.).
CAUTION: The protective heat sleeves must cover
the entire rubber hose and hose to tube connection
portion of both the power steering fluid pressure
and return hoses (Fig. 26).
(8) 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.
(9) After hoses are installed and power steering
system is filled with fluid and cap is installed on res-
ervoir. Start the engine and check for leaks. (See
Pump Installation).
POWER STEERING FLUID RETURN HOSE
Service all power steering hoses with vehicle raised
on hoist. Cap all open ends of hoses, power steering
pump fittings and steering gear ports to prevent
entry of foreign material into the components.
WARNING: POWER STEERING OIL, ENGINE
PARTS AND THE EXHAUST SYSTEM MAY BE
EXTREMELY HOT IF ENGINE HAS BEEN RUNNING.
DO NOT START ENGINE WITH ANY LOOSE OR DIS-
CONNECTED HOSES. DO NOT ALLOW HOSES TO
TOUCH HOT EXHAUST MANIFOLD OR CATALYST.
For part reference and part location for the vehicle
that is being serviced, refer to the following figure
numbers. These show the hose bracket locations,
hose routings and fitting locations by the engine
application of the vehicle. Use these figure numbers
when referring to the removal or installation proce-
dures for the power steering hoses listed below.
REMOVE
(1) Remove cap from power steering fluid reser-
voir.
(2) Using a siphon pump, remove as much power
steering fluid as possible from the power steering
fluid reservoir.
(3) Raise vehicle See Hoisting, Group 0. Put oil
drain pan under vehicle to catch power steering fluid.
(4) Raise the insulating heat sleeve on the power
steering hoses to expose the hose to steel tube con-
nection. Remove hose clamp where rubber portion of
power steering fluid return hose attaches to steel
tube on suspension cradle (Fig. 30). Remove rubber
hose from steel tube and allow power steering fluid
to drain from pump.(5) Remove the power steering fluid return hose
from the power steering pump return hose fitting.
INSTALL
(1) Using a lint free towel, wipe clean the open
power steering hose ends and power steering pump
fitting.
(2) Attach the power steering return hose to the
fitting on the power steering pump. Route hose
smoothly avoiding tight bends or kinking. Hose must
remain away from the exhaust system and not come
in contact with any unfriendly surfaces of the vehi-
cle.
(3) Install the power steering fluid return hose on
the steel tube at the front suspension cradle (Fig.
30).
(4) Install a screw type hose clamp on the power
steering hose to steel tube connection. 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. 30). This is to pre-
vent overheating of the power steering fluid hoses.
(5) When used, position the protective heat sleeves
on the power steering hoses so they cover the connec-
tion to the power steering pump. Then, tie strap the
heat sleeves to the power steering hoses to keep
them in their proper position.
(6) After hoses are installed and power steering
system is filled with fluid and cap is installed on res-
ervoir. Start the engine and check for leaks. (See
Pump Installation).
Fig. 30 Power Steering Return Hose At Steel Tube
NSSTEERING 19 - 21
REMOVAL AND INSTALLATION (Continued)

(6) Remove the pressure fitting/flow control valve
from the power steering pump and remove and dis-
card the O-Ring seal.
ASSEMBLE
(1) Install a new O-Ring seal on the pressure fit-
ting/flow control valve, and wet the O-Ring with
clean fresh power steering fluid.
(2) Install the pressure fitting/flow control valve in
the power steering pump. Tighten the pressure fit-
ting/flow control valve to a torque of 75 N´m (55 ft.
lbs.).
CAUTION: When tightening and torquing the pres-
sure hose at the power steering pump, the hose
should be rotated against the fluid return hose fit-
ting on the pump.(3) Install the power steering fluid pressure hose
in the pressure fitting/flow control valve (Fig. 37).
Tighten the tube nut to a torque of 34 N´m (25 ft.
lbs.)
(4) Install the power steering fluid return hose on
the steel tube at the front suspension cradle (Fig.
36).
(5) Install a screw type hose clamp on the power
steering hose to steel tube connection. 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. 36). This is required
to keep the power steering hoses from becoming
overheated.
(6) When used, properly position the protective
heat sleeves (Fig. 36) on the power steering hoses.
Then, tie strap the heat sleeves to the power steering
hoses to keep them in their proper position.
(7) Fill the power steering system with fluid, bleed
air from system and check that power steering fluid
is at correct level.
SPECIFICATIONS
POWER STEERING SYSTEM SPECIFICATIONS
Flow At 1500 RPM And Minimum Pressure.5.0 to 7.0
Liters/Min (1.3 to 1.9 GPM)
Control Valve Pressure Relief. 9653 to 10342 kPa (1400
to 1500psi)
POWER STEERING PUMP FASTENER TORQUE
SPECIFICATIONS
DESCRIPTION TORQUE
POWER STEERING PUMP:
Flow Control Valve Fitting. . . .75 N´m (55 ft. lbs.)
Mounting Bolts.............54N´m(40ft.lbs.)
Rear Bracket To Engine
Mounting Bolts.............54N´m(40ft.lbs.)
POWER STEERING FLUID HOSES:
Hose Tube Nuts.............34N´m(25ft.lbs.)
Routing Bracket To
Suspension Cradle..........28N´m(21ft.lbs.)
Fig. 36 Return Hose At Steel Tube
Fig. 37 Pressure Hose Connection To Power
Steering Pump
19 - 24 STEERINGNS
DISASSEMBLY AND ASSEMBLY (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)

TIRES AND WHEELS
CONTENTS
page page
TIRES.................................. 1WHEELS................................ 9
TIRES
INDEX
page page
DESCRIPTION AND OPERATION
RADIAL-PLY TIRES....................... 2
REPLACEMENT TIRES.................... 3
SPARE TIRE (TEMPORARY)................ 2
TIRE INFLATION PRESSURES.............. 2
TIRE INFORMATION...................... 1
TIRE PRESSURE FOR HIGH-SPEED DRIVING . . 3
DIAGNOSIS AND TESTING
LEAD CORRECTION CHART................ 4
PRESSURE GAUGES..................... 3
TIRE NOISE OR VIBRATION................ 4TIRE WEAR PATTERNS.................... 4
TREAD WEAR INDICATORS................ 3
SERVICE PROCEDURES
REPAIRING TIRE LEAKS................... 6
TIRE AND WHEEL MATCH MOUNTING........ 6
TIRE AND WHEEL ROTATION (NON-
DIRECTIONAL THREAD PATTERN).......... 6
CLEANING AND INSPECTION
CLEANING TIRES........................ 7
SPECIFICATIONS
TIRE SPECIFICATIONS.................... 8
DESCRIPTION AND OPERATION
TIRE INFORMATION
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
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, aspect ratio and speed rating are
encoded in the letters and numbers imprinted on the
side wall of the tire. Refer to the chart to decipher
the tire identification code (Fig. 1).
Performance tires will have a speed rating letter
after the aspect ratio number. The speed rating is not
always printed on the tire sidewall. The letterSindi-
cates that the tire is speed rated up to 112 mph.
²Qup to 100 mph
²Tup to 118 mph
²Uup to 124 mph
²Hup to 130 mph
²Vup to 149 mph
²Zmore than 149 mph (consult the tire manu-
facturer for the specific speed rating)
An All Season type tire will have eitherM+S,M
&SorM±S(indicating mud and snow traction)
imprinted on the side wall.
TIRE CHAINS
This vehicle was designed to allow the use of a
specified type of snow chain on the tires. Only com-
pact snow chains or other traction aidsmeeting SAE
type ªClass Sº specifications may be used.Any style
NSTIRES AND WHEELS 22 - 1

snow chain or other type of traction aid is not
to be used on the compact spare tire.
RADIAL-PLY TIRES
Radial-ply tires improve handling, tread life, ride
quality and decrease rolling resistance.
Radial-ply tires must always be used in sets of four
and under no circumstances should they be used on
the front only. They may be mixed with a temporary
spare tire when necessary. A maximum speed of 50
MPH is recommended while a temporary spare is in
use.
Radial-ply tires have the same load-carrying capac-
ity as other types of tires of the same size. They also
use the same recommended inflation pressures.
The use of oversized tires, either in the front or
rear of the vehicle, can cause vehicle drive train fail-
ure. This could also cause inaccurate wheel speed
signals when the vehicle is equipped with Anti-Lock
Brakes.
It is recommended that tires from different manu-
factures NOT be mixed. The proper tire pressure
should be maintained on all four tires. For proper
tire pressure refer to the Tire Inflation Pressure
Placard located in the glove box.
SPARE TIRE (TEMPORARY)
The temporary spare tire is designed for emer-
gency use only. The original tire should be repaired
and reinstalled at the first opportunity, or replaced
with a new. Do not exceed speeds of 50 MPH when
the temporary spare tire is in use on the vehicle.
Refer to the Owner's Manual for complete details.
TIRE INFLATION PRESSURES
WARNING: OVER OR UNDER INFLATED TIRES
CAN AFFECT VEHICLE HANDLING. THE TIRE CAN
FAIL SUDDENLY, RESULTING IN LOSS OF VEHICLE
CONTROL.
Under inflation causes rapid shoulder wear of the
tire tread and tire flexing. This can result in failure
of the tire. (Fig. 2).
Over inflation causes rapid center wear and loss of
the tire's ability tocushion shocks (Fig. 3).
Fig. 1 Tire Size Identification
Fig. 2 Under Inflation Wear
Fig. 3 Over Inflation Wear
22 - 2 TIRES AND WHEELSNS
DESCRIPTION AND OPERATION (Continued)

Improper inflation can cause:
²Uneven wear patterns
²Reduced tread life
²Reduced fuel economy
²Unsatisfactory ride
²The vehicle to drift.
Proper tire air inflation pressure specifications can
be found on the Vehicle Tire Placard provided with
the vehicle. See owner's manual.
Tire pressures have been chosen to provide safe
operation, vehicle stability, and a smooth ride. Tire
pressure should be checked cold once per month.
Check tire pressure more frequently when the
weather temperature varies widely. Tire pressure will
decrease when the outdoor temperature drops.
Tire inflation pressures specified on the placard
are always cold inflation pressure. Cold inflation
pressure is obtained after the vehicle has not been
operated for at least 3 hours, or the vehicle is driven
less than one mile after being inoperative for 3
hours. Tire inflation pressures may increase from 2
to 6 pounds per square inch (psi) during operation.
Do not reduce this normal pressure build-up.
TIRE PRESSURE FOR HIGH-SPEED DRIVING
Chrysler Corporation advocates driving at safe
speeds within posted speed limits. Where speed lim-
its allow the vehicle to be driven at high speeds, cor-
rect tire inflation pressure is very important. For
speeds up to and including 75 mph (120 km/h), tires
must be inflated to the pressures shown on the tire
placard.
Vehicles loaded to the maximum capacity should
not be driven at speeds above 75 mph (120 km/h).
For emergency vehicles that are driven at speeds
over 90 mph (144 km/h), special high-speed tires
must be used. Consult tire manufacturer for correct
inflation pressure recommendations.
REPLACEMENT TIRES
The original equipment tires provide a proper bal-
ance of many characteristics such as:
²Ride
²Noise
²Handling
²Durability
²Tread life
²Traction
²Rolling resistance
²Speed capability
It is recommend that tires equivalent to the origi-
nal equipment tires be used when replacement is
needed.
Failure to use equivalent replacement tires may
adversely affect the safety and handling of the vehicle.
The use of oversize tires not listed in the specifica-
tion charts may cause interference with vehicle com-
ponents. Under extremes of suspension and steering
travel, interference with vehicle components may
cause tire damage.
WARNING: FAILURE TO EQUIP THE VEHICLE WITH
TIRES HAVING ADEQUATE SPEED CAPABILITY
CAN RESULT IN SUDDEN TIRE FAILURE.
DIAGNOSIS AND TESTING
PRESSURE GAUGES
A quality air pressure gauge is recommended to
check tire pressure. After checking the air pressure,
replace valve cap finger tight.
TREAD WEAR INDICATORS
Tread wear indicators are molded into the bottom
of the tread grooves. When tread depth is 1.6 mm
(1/16 in.), the tread wear indicators will appear as a
13 mm (1/2 in.) band (Fig. 4).
Tire replacement is necessary when indicators
appear in two or more grooves or if localized balding
occurs.
Fig. 4 Tread Wear Indicators
NSTIRES AND WHEELS 22 - 3
DESCRIPTION AND OPERATION (Continued)

The High Side service port is a two piece port and
is serviceable. The Low Side service port is not ser-
viceable, the suction line would have to be replaced.
REAR BLOWER SPEED SWITCH
The rear blower speed switch controls the rear
blower with the choice of low and high speeds. When
the switch is on it allows the blower speed switch
located on the rear headliner to control rear blower
speed. This switch will override the rear headliner
blower switch. For operation instructions refer to the
Owner's Manual. The rear blower speed switch is
serviced separately from the A/C control module. For
service procedures, refer to Group 8E, Instrument
Panel And Gauges.
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
Fig. 1 A/C Pressure Transducer
Fig. 2 Valve Service Ports
NSHEATING AND AIR CONDITIONING 24 - 3
DESCRIPTION AND OPERATION (Continued)

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)