2002 JEEP LIBERTY air vents

REAR WASHER SYSTEM
The washer system components should be
inspected periodically, not just when washer perfor-
mance problems are experienced. This inspection
should include the following points:
(1) Check for ice or other foreign material in the
washer reservoir. If contaminated, clean and flush
the washer system. (Refer to 8 - ELECTRICAL/
REAR WIPERS/WASHERS - CLEANING).
(2) Inspect the washer plumbing for pinched, leak-
ing, deteriorated, or incorrectly routed hoses and
damaged or disconnected hose fittings. Replace dam-
aged or deteriorated hoses and hose fittings. Leaking
washer hoses can sometimes be repaired by cutting
the hose at the leak and splicing it back together
using an in-line connector fitting. Similarly, sections
of deteriorated hose can be cut out and replaced by
splicing in new sections of hose using in-line connec-
tor fittings. Whenever routing a washer hose or a
wire harness containing a washer hose, it must be
routed away from hot, sharp, or moving parts. Also,
sharp bends that might pinch the washer hose must
be avoided.
REAR CHECK VALVE
DESCRIPTION
A rear washer system check valve is standard
equipment on this model (Fig. 3). The rear check
valve is located in the washer plumbing between the
rear roof header and the roof outer panel near the
rear washer nozzle. The rear check valve consists of
a molded plastic body with a round center sectionand barbed hose nipples at each end. An arrow for-
mation molded into the center section of the valve
body indicates the direction of flow through the
valve. The rear check valve cannot be adjusted or
repaired and, if faulty or damaged, it must be
replaced.
OPERATION
The rear check valve prevents washer fluid from
draining out of the rear washer supply hoses back to
the washer reservoir. This drain-back would result in
a lengthy delay from when the rear washer switch is
actuated until washer fluid was dispensed through
the rear washer nozzle, because the washer pump
would have to refill the rear washer plumbing from
the reservoir to the nozzle. The check valve also pre-
vents washer fluid from siphoning through the rear
washer nozzle after the rear washer system is turned
Off.
Within the check valve body, a small check valve is
held in place against a seat by a small coiled spring
to restrict flow through the unit until the valve is
unseated by a predetermined inlet fluid pressure.
When the washer pump pressurizes and pumps
washer fluid from the reservoir through the rear
washer plumbing, the fluid pressure overrides the
spring pressure applied to the check ball within the
valve and unseats the valve, allowing washer fluid to
flow toward the rear washer nozzle. When the
washer pump stops operating, spring pressure seats
the check valve and fluid flow in either direction
within the rear washer plumbing is prevented.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the Center High Mounted Stop Lamp
(CHMSL) unit from the rear of the roof panel. (Refer
to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTERI-
OR/CENTER HIGH MOUNTED STOP LAMP UNIT
- REMOVAL).
WARNING: THE EDGES OF THE SHEET METAL
AROUND THE CENTER HIGH MOUNTED STOP
LAMP MOUNTING HOLE IN THE ROOF PANEL.
TAKE THE PROPER PRECAUTIONS TO AVOID PER-
SONAL INJURY.
(3) Reach through the CHMSL unit mounting hole
in the rear of the roof panel to access and disconnect
the rear washer hose at the barbed nipple of the rear
washer nozzle (Fig. 4).
(4) Pull the rear washer hose through the CHMSL
unit mounting hole far enough to access and discon-
nect the headliner washer hose from the barbed nip-
ple of the rear check valve.
Fig. 3 Rear Check Valve
1 - INLET NIPPLE
2 - REAR CHECK VALVE
3 - OUTLET NIPPLE
4 - FLOW DIRECTION ARROW
8R - 34 REAR WIPERS/WASHERSKJ
REAR WIPERS/WASHERS (Continued)

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE OIL LEAK
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24km (15 miles), and
repeat inspection.If the oil leak source is not pos-
itively identified at this time, proceed with the air
leak detection test method.
Air Leak Detection Test Method
(1) Disconnect the breather cap to air cleaner hose
at the breather cap end. Cap or plug breather cap
nipple.
(2) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(3) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
(4) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provide the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
(5) If the leakage occurs at the rear oil seal area,
refer to the section, Inspection for Rear Seal Area
Leak.
(6) If no leaks are detected, turn off the air supply
and remove the air hose and all plugs and caps.
Install the PCV valve and breather cap hose.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, camshaft bore
cup plugs oil galley pipe plugs, oil filter runoff, and
main bearing cap to cylinder block mating sur-
faces.
(4) If no leaks are detected, pressurize the crank-
case as outlined in the, Inspection (Engine oil Leaks
in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
DIAGNOSIS AND TESTING - ENGINE OIL
PRESSURE
(1) Remove oil pressure sending unit (Fig. 70)and
install gauge assembly C-3292.
(2) Run engine until thermostat opens.
(3) Oil Pressure:
²Curb IdleÐ25 Kpa (4 psi) minimum
²3000 rpmÐ170 - 550 KPa (25 - 80 psi)
(4) If oil pressure is 0 at idle, shut off engine.
Check for a clogged oil pick-up screen or a pressure
relief valve stuck open.
9 - 60 ENGINE - 3.7LKJ
LUBRICATION (Continued)

DIAGNOSIS AND TESTING - REAR SEAL AREA
LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, camshaft bore
cup plugs, oil galley pipe plugs, oil filter runoff,
and main bearing cap to cylinder block mating sur-
faces. See Engine, for proper repair procedures of
these items.
(4) If no leaks are detected, pressurized the crank-
case as outlined in the section, Inspection (Engine oil
Leaks in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks or
scratches. The crankshaft seal flange is specially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled. (Refer to 9 - ENGINE - DIAGNOSIS AND
TESTING), under the Oil Leak row, for components
inspections on possible causes and corrections.
(7) After the oil leak root cause and appropriate
corrective action have been identified, (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - REAR - REMOVAL).
OIL
STANDARD PROCEDURE - ENGINE OIL
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
Use an engine oil that is API Service Grade Certi-
fied. MOPARtprovides engine oils that conform to
this service grade.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. Use only engine oils with multi-
Fig. 70 Oil Pressure Sending Unit -Typical
1 - BELT
2 - OIL PRESSURE SENSOR
3 - OIL FILTER
4 - ELEC. CONNECTOR
KJENGINE - 3.7L 9 - 61
LUBRICATION (Continued)

(7) Crank engine until maximum pressure is
reached on gage. Record this pressure as #1 cylinder
pressure.
(8) Repeat the previous step for all remaining cyl-
inders.
(9) Compression should not be less than 689 kPa
(100 psi) and not vary more than 25 percent from cyl-
inder to cylinder.
(10) If one or more cylinders have abnormally low
compression pressures, repeat the compression test.
(11) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question.The recommended com-
pression pressures are to be used only as a
guide to diagnosing engine problems. An engine
should not be disassembled to determine the
cause of low compression unless some malfunc-
tion is present.
DIAGNOSIS AND TESTING - ENGINE OIL LEAK
INSPECTION
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair as necessary.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24 km (15 miles), and
repeat inspection.
(5)If the oil leak source is not positively
identified at this time, proceed with the air leak
detection test method as follows:
²Disconnect the fresh air hose (make-up air) at
the cylinder head cover and plug or cap the nipple on
the cover.
²Remove the PCV valve hose from the cylinder
head cover. Cap or plug the PCV valve nipple on the
cover.
²Attach an air hose with pressure gauge and reg-
ulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.²Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provides the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
²If the leakage occurs at the crankshaft rear oil
seal area, refer to the section, Inspection for Rear
Seal Area Leak.
(6) If no leaks are detected, turn off the air supply.
Remove the air hose, all plugs, and caps. Install the
PCV valve and fresh air hose (make-up air). Proceed
to next step.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
NOTE: If oil leakage is observed at the dipstick tube
to block location; remove the tube, clean and reseal
using MoparTStud & Bearing Mount (press fit tube
applications only), and for O-ring style tubes,
remove tube and replace the O-ring seal.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak. If a leak is
present in this area, remove transmission for further
inspection.
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, oil gallery cup
plug, bedplate to cylinder block mating surfaces
and seal bore. See proper repair procedures for
these items.
(4) If no leaks are detected, pressurize the crank-
case as previously described.
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
9s - 4 ENGINEKJ
ENGINE - 2.4L (Continued)

CYLINDER HEAD COVER
REMOVAL
(1) Remove intake manifold. (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL)
(2) Remove ignition coil and spark plug wires.
(3) Disconnect PCV and make-up air hoses from
cylinder head cover.
(4) Remove cylinder head cover bolts.
(5) Remove cylinder head cover from cylinder
head.
CLEANING
Clean cylinder head and cover mating surfaces
using a suitable solvent.
INSPECTION
Inspect cover rails for flatness.
INSTALLATION
NOTE: Replace spark plug well seals and bolt
assemblies when installing a new cylinder head
cover gasket.
(1) Install new cylinder head cover gaskets and
spark plug well seals (Fig. 22).
(2) Replace cylinder head cover bolt assemblies
(Fig. 23).
CAUTION: Do not allow oil or solvents to contact
the timing belt as they can deteriorate the rubber
and cause tooth skipping.(3) Apply MopartEngine RTV GEN II at the
camshaft cap corners and at the top edges of the 1/2
round seal (Fig. 24).
Fig. 22 Spark Plug Well Seals
Fig. 23 Cylinder Head Cover Bolt Assembly
Fig. 24 Sealer Locations - Typical
1 ± SEALER LOCATION
9s - 26 ENGINEKJ

BODY
TABLE OF CONTENTS
page page
BODY
WARNING
SAFETY PRECAUTIONS AND WARNINGS . . . 1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - WATER LEAKS . 2
DIAGNOSIS AND TESTING - WIND NOISE . . . 3
STANDARD PROCEDURE
STANDARD PROCEDURE - BODY
LUBRICATION.........................3
STANDARD PROCEDURE - HEAT STAKING . . 3
SPECIFICATIONS........................4
SPECIAL TOOLS
BODY...............................5BODY STRUCTURE.......................6
HOOD................................119
DOOR - FRONT........................121
DOORS - REAR........................128
SWING GATE..........................135
EXTERIOR............................140
INSTRUMENT PANEL....................147
INTERIOR.............................156
PAINT................................162
SEATS...............................164
STATIONARY GLASS....................172
SUNROOF.............................175
WEATHERSTRIP/SEALS..................185
BODY
WARNING
SAFETY PRECAUTIONS AND WARNINGS
WARNING: EYE PROTECTION SHOULD BE USED
WHEN SERVICING GLASS COMPONENTS. PER-
SONAL INJURY CAN RESULT.
²USE A OSHA APPROVED BREATHING FILTER
WHEN SPRAYING PAINT OR SOLVENTS IN A CON-
FINED AREA. PERSONAL INJURY CAN RESULT.
²AVOID PROLONGED SKIN CONTACT WITH
PETROLEUM OR ALCOHOL±BASED CLEANING
SOLVENTS. PERSONAL INJURY CAN RESULT.
²DO NOT STAND UNDER A HOISTED VEHICLE
THAT IS NOT PROPERLY SUPPORTED ON SAFETY
STANDS. PERSONAL INJURY CAN RESULT.
CAUTION: When holes must be drilled or punched
in an inner body panel, verify depth of space to the
outer body panel, electrical wiring, or other compo-
nents. Damage to vehicle can result.
²Do not weld exterior panels unless combustible
material on the interior of vehicle is removed from
the repair area. Fire or hazardous conditions, can
result.
²Always have a fire extinguisher ready for use
when welding.
²Disconnect the negative (-) cable clamp from
the battery when servicing electrical components
that are live when the ignition is OFF. Damage to
electrical system can result.²Do not use abrasive chemicals or compounds
on painted surfaces. Damage to finish can result.
²Do not use harsh alkaline based cleaning sol-
vents on painted or upholstered surfaces. Damage
to finish or color can result.
²Do not hammer or pound on plastic trim panel
when servicing interior trim. Plastic panels can
break.
DaimlerChrysler Corporation uses many different
types of push-in fasteners to secure the interior and
exterior trim to the body. Most of these fasteners can
be reused to assemble the trim during various repair
procedures. At times, a push-in fastener cannot be
removed without damaging the fastener or the com-
ponent it is holding. If it is not possible to remove a
fastener without damaging a component or body, cut
or break the fastener and use a new one when
installing the component. Never pry or pound on a
plastic or pressed-board trim component. Using a
suitable fork-type prying device, pry the fastener
from the retaining hole behind the component being
removed. When installing, verify fastener alignment
with the retaining hole by hand. Push directly on or
over the fastener until it seats. Apply a low-force pull
to the panel to verify that it is secure.
When it is necessary to remove components to ser-
vice another, it should not be necessary to apply
excessive force or bend a component to remove it.
Before damaging a trim component, verify hidden
fasteners or captured edges holding the component in
place.
KJBODY 23 - 1

electric cooling fan operations. The switch is located
on the discharge line near the compressor. The
switch is screwed onto a fitting that contains a
Schrader-type valve, which allows the switch to be
serviced without discharging the refrigerant system.
The discharge line fitting is equipped with an O-ring
to seal the switch connection.
OPERATION
The A/C high pressure switch is connected in series
electrically with the A/C low pressure switch between
ground and the Powertrain Control Module (PCM).
The switch contacts open and close causing the PCM
to turn the compressor clutch on and off. This pre-
vents compressor operation when the discharge line
pressure approaches high levels, and also reduces
electrical surging from compressor clutch engage-
ment.
The A/C high pressure switch controls the electric
cooling fan operation by monitoring refrigerant line
pressures. When the discharge line pressure rises
above 1900 to 2200 kPa (280 to 320 psi) the fan will
turn on. The cooling fan will turn off when the dis-
charge line pressure drops to 1600 kPa (235 psi).
The A/C high pressure switch controls the A/C
clutch operation by disengaging the clutch when the
discharge line pressure rises above 3100 to 3375 kPa
(450 to 490 psi). The switch contacts will close and
allow A/C clutch engagement when the discharge line
pressure drops to 1860 to 2275 kPa (270 to 330 psi).
The A/C high pressure switch is a factory-cali-
brated unit. The switch cannot be adjusted or
repaired and, if faulty or damaged, it must be
replaced.
DIAGNOSIS AND TESTING - A/C HIGH
PRESSURE SWITCH
Before performing diagnosis of the A/C high pres-
sure switch, verify that the refrigerant system has
the correct refrigerant charge. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE - REFRIGERANT SYSTEM
CHARGE)
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the A/C high pressure switch wire har-
ness connector from the switch on the refrigerant
system fitting.
(3) On the four terminal A/C high pressure switch,
check for continuity between terminals C and D. On
the two terminal A/C high pressure switch, check for
continuity between both terminals of the switch.
There should be continuity. If OK, test and repair theA/C switch sense circuit as required. If not OK,
replace the faulty switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the
A/C high pressure switch, which is mounted to a fit-
ting on the non-flexible section of the discharge line
nearest the compressor.
(3) Unscrew the A/C high pressure switch from the
discharge line fitting.
(4) Remove the A/C high pressure switch from the
vehicle.
(5) Remove the O-ring seal from the discharge line
fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the discharge line fitting.
Use only the specified O-rings as they are made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the com-
pressor in the vehicle(Refer to 24 - HEATING & AIR
CONDITIONING - SPECIFICATIONS). (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT OIL - DESCRIPTION)
(2) Install and tighten the a/c high pressure switch
on the discharge line fitting. The switch should be
hand-tightened onto the discharge line fitting.
(3) Plug the wire harness connector into the a/c
high pressure switch.
(4) Connect the battery negative cable.
A/C LOW PRESSURE SWITCH
DESCRIPTION
The a/c low pressure switch is located on the top of
the accumulator. The switch is screwed onto an accu-
mulator fitting that contains a Schrader-type valve,
which allows the switch to be serviced without dis-
charging the refrigerant system. The accumulator fit-
ting is equipped with an O-ring to seal the switch
connection.
OPERATION
The a/c low pressure switch is connected in series
electrically with the a/c high pressure switch,
between ground and the Powertrain Control Module
(PCM). The switch contacts open and close causing
the PCM to turn the a/c compressor clutch on and
off. This regulates the refrigerant system pressure
and controls evaporator temperature. Controlling the
evaporator temperature prevents condensate water
24 - 18 CONTROLSKJ
A/C HIGH PRESSURE SWITCH (Continued)

used to charge the refrigerant system with R-134a
refrigerant. Refer to the operating instructions sup-
plied by the equipment manufacturer for proper care
and use of this equipment.
SPECIFICATIONS - CHARGE CAPACITY
The R-134a refrigerant system charge capacity for
this vehicle is 0.737 kilograms (1.63 pounds).
A/C COMPRESSOR
DESCRIPTION
DESCRIPTION
The air conditioning system uses a Sanden
PXF-18, reciprocating swash plate-type compressor
on all models. This compressor has a fixed displace-
ment of 180 cubic centimeters (10.984 cubic inches),
and has both the suction and discharge ports located
on the cylinder head. A label identifying the use of
R-134a refrigerant is located on the compressor.
DESCRIPTION - HIGH PRESSURE RELIEF
VALVE
A high pressure relief valve is located on the com-
pressor cylinder head, which is on the rear of the
compressor. This mechanical valve is designed to
vent refrigerant from the system to protect against
damage to the compressor and other system compo-
nents, caused by condenser air flow restriction or an
overcharge of refrigerant.
OPERATION
OPERATION
The compressor is driven by the engine through an
electric clutch, drive rotor and belt arrangement. The
compressor is lubricated by refrigerant oil that is cir-
culated throughout the refrigerant system with the
refrigerant.
The compressor draws in low-pressure refrigerant
vapor from the evaporator through its suction port. It
then compresses the refrigerant into a high-pressure,
high-temperature refrigerant vapor, which is then
pumped to the condenser through the compressor dis-
charge port.
The compressor cannot be repaired. If faulty or
damaged, the entire compressor assembly must be
replaced. The compressor clutch, pulley and clutch
coil are available for service.
OPERATION - HIGH PRESSURE RELIEF VALVE
The high pressure relief valve vents the system
when a discharge pressure of 3445 to 4135 kPa (500
to 600 psi) or above is reached. The valve closes
when a minimum discharge pressure of 2756 kPa
(400 psi) is reached.
The high pressure relief valve vents only enough
refrigerant to reduce the system pressure, and then
re-seats itself. The majority of the refrigerant is con-
served in the system. If the valve vents refrigerant, it
does not mean that the valve is faulty.
The high pressure relief valve is a factory-cali-
brated unit. The valve cannot be adjusted or
repaired, and must not be removed or otherwise dis-
turbed. The valve is only serviced as a part of the
compressor assembly.
DIAGNOSIS AND TESTING - A/C COMPRESSOR
NOISE
When investigating an air conditioning related
noise, you must first know the conditions under
which the noise occurs. These conditions include:
weather, vehicle speed, transmission in gear or neu-
tral, engine speed, engine temperature, and any
other special conditions. Noises that develop during
air conditioning operation can often be misleading.
For example: What sounds like a failed front bearing
or connecting rod, may be caused by loose bolts, nuts,
mounting brackets, or a loose compressor clutch
assembly.
Drive belts are speed sensitive. At different engine
speeds and depending upon belt tension, belts can
develop noises that are mistaken for a compressor
noise. Improper belt tension can cause a misleading
noise when the compressor clutch is engaged, which
may not occur when the compressor clutch is disen-
gaged. Check the serpentine drive belt condition and
tension as described in Cooling before beginning this
procedure.
(1) Select a quiet area for testing. Duplicate the
complaint conditions as much as possible. Switch the
compressor on and off several times to clearly iden-
tify the compressor noise. Listen to the compressor
while the clutch is engaged and disengaged. Probe
the compressor with an engine stethoscope or a long
screwdriver with the handle held to your ear to bet-
ter localize the source of the noise.
(2) Loosen all of the compressor mounting hard-
ware and retighten. Tighten the compressor clutch
mounting nut. Be certain that the clutch coil is
mounted securely to the compressor, and that the
clutch plate and rotor are properly aligned and have
the correct air gap. (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/A/C COMPRESSOR
CLUTCH - INSTALLATION)
24 - 42 PLUMBINGKJ
PLUMBING (Continued)