2002 JEEP LIBERTY air conditioning

HAZARD SWITCH
DESCRIPTION
The hazard switch is integral to the hazard switch
module, which is secured near the center of instrument
panel just above the radio (Fig. 21). Only the hazard
switch button is visible through a dedicated, round, bev-
eled opening on the outer surface of the instrument
panel between the two center panel outlets of the heater
and air conditioning system. A red, stencil-like Interna-
tional Control and Display Symbol icon for ªHazard
Warningº identifies the hazard switch button. On the
opposite end of the black, molded plastic hazard switch
module housing from the switch button is an integral
connector receptacle and a stamped steel mounting
bracket with two latch feature tabs that extend down-
ward, while a short dowel-like alignment pin is integral
to each side of the housing just below the switch button.
The switch module is connected to the vehicle electrical
system through a dedicated take out and connector of
the instrument panel wire harness. Within the hazard
switch module housing is the hazard switch circuitry
and an electronic circuit board with the integral combi-
nation flasher circuitry. The electronic combination
flasher circuitry performs both the hazard flasher and
turn signal flasher functions.
The hazard switch module cannot be adjusted or
repaired and, if faulty or damaged, the unit must be
replaced.
OPERATION
The hazard switch button is slightly recessed in the
instrument panel when the switch is in the Off position,
and latches at a position that is flush with the outer
surface of the instrument panel when in the On posi-tion. The hazard switch module produces an audible
clicking sound that emulates the sound of a conven-
tional flasher whenever the turn signals or the hazard
warning system are activated. The hazard switch mod-
ule receives battery current on a fused B(+) circuit from
a fuse in the Junction Block (JB) at all times for oper-
ation of the hazard warning, and on a fused ignition
switch output (run) circuit from another fuse in the JB
whenever the ignition switch is in the On position for
operation of the turn signals. The module receives a
path to ground through a splice block located in the
instrument panel wire harness with an eyelet terminal
connector that is secured by a nut to a ground stud on
the driver side instrument panel end bracket near the
JB. Inputs to and outputs from the hazard switch mod-
ule include:
²Panel Lamps Dimmer Input- A non-service-
able incandescent bulb soldered onto the hazard
switch module circuit board provides illumination of
the switch button when the exterior lighting is
turned On through an input received on the fused
panel lamps dimmer switch signal circuit. However,
this bulb flashes on and off at full intensity whenever
the hazard switch button is in the On position,
regardless of the status of the exterior lighting.
²Hazard Switch Input- The combination
flasher circuitry of the hazard switch module receives
an internal ground input from the hazard switch to
request hazard flasher operation.
²Multi-Function Switch Input- The combina-
tion flasher circuitry of the hazard switch module
receives separate ground inputs from the turn signal
switch circuitry of the multi-function switch on right
and left turn switch sense circuits to request right or
left turn signal flasher operation.
²Body Control Module Input- The Body Con-
trol Module (BCM) can request hazard flasher opera-
tion by providing a ground path to the combination
flasher circuitry of the hazard switch module through
a hazard lamp control circuit.
²Turn Signal Output- The combination flasher
circuitry within the hazard switch module responds
to the flasher request inputs by energizing and
de-energizing two miniature relays on the module
circuit board. These relays control the switch output
through the right and left turn signal circuits. One
relay controls the right lamps, while the other con-
trols the left.
Because of active electronic elements within the
hazard switch module, it cannot be tested with con-
ventional automotive electrical test equipment. If the
hazard switch module is believed to be faulty, replace
the switch with a known good unit to confirm system
operation.
Fig. 21 Hazard Switch
1 - HAZARD SWITCH BUTTON
2 - SCREW (1)
3 - MOUNTING BRACKET TABS
KJLAMPS/LIGHTING - EXTERIOR 8L - 29

INSTALLATION
(1) Position the front lamp unit to the front
bumper fascia.
(2) Reconnect the wire harness connector(s) for the
front lamp unit to the lamp socket pigtail wire(s).
(3) Engage the tab on the inboard end of the front
lamp unit housing into the receptacle in the front
bumper fascia.
(4) Position the outboard end of the front lamp
unit housing to the front bumper fascia.
(5) Install and tighten the screw that secures the
outboard end of the front lamp unit housing to the
front bumper fascia (Fig. 19). Tighten the screw to 2
N´m (20 in. lbs.).
(6) Reconnect the battery negative cable.
FRONT POSITION LAMP BULB
REMOVAL
The front position lamps are integral to the head-
lamp units on vehicles manufactured for certain mar-
kets where these lamps are required.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the headlamp unit from the front grille
opening reinforcement. (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - EXTERIOR/HEADLAMP UNIT
- REMOVAL).
(3) Rotate the front position lamp socket near the
bottom of the headlamp unit housing counterclock-
wise about 30 degrees (Fig. 20).
(4) Pull the socket and bulb straight out of the
headlamp unit housing.(5) Pull the bulb straight out of the front position
lamp socket.
INSTALLATION
The front position lamps are integral to the head-
lamp units on vehicles manufactured for certain mar-
kets where these lamps are required.
CAUTION: Always use the correct bulb size and
type for replacement. An incorrect bulb size or type
may overheat and cause damage to the lamp, the
socket and/or the lamp wiring.
(1) Align the base of the bulb with the receptacle
in the front position lamp socket.
(2) Push the bulb straight into the front position
lamp socket until it is firmly seated.
(3) Align the socket and bulb with the socket open-
ing near the bottom of the headlamp unit housing
(Fig. 20).
(4) Push the socket and bulb straight into the
headlamp unit housing until it is firmly seated
(5) Rotate the front position lamp socket near the
bottom of the headlamp unit housing clockwise about
30 degrees.
(6) Reinstall the headlamp unit onto the grille
opening reinforcement. (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - EXTERIOR/HEADLAMP UNIT
- INSTALLATION).
(7) Reconnect the battery negative cable.
(8) Confirm proper headlamp unit alignment.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/HEADLAMP UNIT - ADJUSTMENTS).
HAZARD SWITCH
DESCRIPTION
The hazard switch is integral to the hazard switch
module, which is secured near the center of instru-
ment panel just above the radio (Fig. 21). Only the
hazard switch button is visible through a dedicated,
round, beveled opening on the outer surface of the
instrument panel between the two center panel out-
lets of the heater and air conditioning system. A red,
stencil-like International Control and Display Symbol
icon for ªHazard Warningº identifies the hazard
switch button. On the opposite end of the black,
molded plastic hazard switch module housing from
the switch button is an integral connector receptacle
and a stamped steel mounting bracket with two latch
feature tabs that extend downward, while a short
dowel-like alignment pin is integral to each side of
the housing just below the switch button. The switch
module is connected to the vehicle electrical system
through a dedicated take out and connector of the
instrument panel wire harness. Within the hazard
Fig. 20 Front Position Lamp Bulb Remove/Install
1 - HEADLAMP HOUSING
2 - SOCKET
3 - BULB
8Ls - 28 LAMPSKJ
FRONT LAMP UNIT (Continued)

PASSENGER AIRBAG
DESCRIPTION
The rearward facing surface of the injection
molded, thermoplastic passenger airbag door is the
most visible part of the passenger airbag (Fig. 23).
The passenger airbag door is located above the glove
box opening in front of the front seat passenger seat-
ing position on the instrument panel. The integral
upper mounting flange is secured with five screws
and the lower mounting flange with six screws to the
instrument panel structural support. The passenger
airbag door includes an integral air conditioning
panel outlet housing and an integral side window
demister outlet. An integral stamped metal bracket
that reinforces the upper airbag door mounting
flange is secured to the back of the door unit with
heat stakes. The upper airbag door fasteners and
mounting flange are concealed beneath the instru-
ment panel top cover, while the lower fasteners and
mounting flange are concealed beneath a bezel on the
instrument panel above the glove box opening.
Located behind the passenger airbag door within
the instrument panel is the passenger airbag unit
(Fig. 24). The passenger airbag unit used in this
model is a multistage, Next Generation-type that
complies with revised federal airbag standards to
deploy with less force than those used in some prior
models. The passenger airbag unit consists of a
molded, glass-filled nylon plastic housing, a molded
plastic inner airbag cushion cover, the airbag cush-
ion, and the airbag inflator. The airbag housing con-tains the airbag inflator, while the inner cover
contains the folded airbag cushion. The inner cover
completely encloses the airbag cushion and is perma-
nently retained to the housing. The passenger airbag
unit is secured by two screws on each side to two
stamped metal mounting brackets that are fastened
with screws to the instrument panel structural sup-
port. The airbag cushion is constructed of a coated
nylon fabric. The airbag inflator is a dual-initiator,
hybrid-type unit that is secured to and sealed within
the airbag housing. A short four-wire pigtail harness
with a keyed, yellow connector insulator connects the
two inflator initiators to the vehicle electrical system
through a dedicated take out and connector of the
instrument panel wire harness.
The passenger airbag cannot be repaired, and must
be replaced if deployed, faulty, or in any way dam-
aged. The passenger airbag door and the passenger
airbag mounting brackets are available for separate
service replacement.
OPERATION
The multistage passenger airbag is deployed by
electrical signals generated by the Airbag Control
Module (ACM) through the passenger airbag squib 1
and squib 2 circuits to the two initiators in the air-
bag inflator. By using two initiators, the airbag can
be deployed at multiple levels of force. The force level
is controlled by the ACM to suit the monitored
impact conditions by providing one of three delay
intervals between the electrical signals provided to
the two initiators. The longer the delay between
these signals, the less forcefully the airbag will
deploy.
Fig. 23 Passenger Airbag Door
1 - PASSENGER AIRBAG DOOR
2 - DEMISTER OUTLET
3 - PANEL OUTLET
4 - BEZEL
5 - GLOVE BOX
Fig. 24 Passenger Airbag Unit
1 - PIGTAIL WIRE CONNECTOR
2 - RETAINER
3 - HOUSING
4 - INNER COVER
KJRESTRAINTS 8O - 27

VACUUM RESERVOIR
DESCRIPTION
The vacuum reservoir is a plastic storage tank con-
nected to an engine vacuum source by vacuum lines.
OPERATION
The vacuum reservoir is used to supply the vac-
uum needed to maintain proper speed control opera-
tion when engine vacuum drops, such as in climbing
a grade while driving. A one-way check valve is used
in the vacuum line between the reservoir and the
vacuum source. This check valve is used to trap
engine vacuum in the reservoir. On certain vehicle
applications, this reservoir is shared with the heat-
ing/air-conditioning system. The vacuum reservoir
cannot be repaired and must be replaced if faulty.
DIAGNOSIS AND TESTING - VACUUM
RESERVOIR
(1) Disconnect vacuum hose at speed control servo
and install a vacuum gauge into the disconnected
hose.
(2) Start engine and observe gauge at idle. Vac-
uum gauge should read at least ten inches of mer-
cury.
(3) If vacuum is less than ten inches of mercury,
determine source of leak. Check vacuum line to
engine for leaks. Also check actual engine intake
manifold vacuum. If manifold vacuum does not meet
this requirement, check for poor engine performance
and repair as necessary.
(4) If vacuum line to engine is not leaking, check
for leak at vacuum reservoir. To locate and gain
access to reservoir, refer to Vacuum Reservoir Remov-
al/Installation in this group. Disconnect vacuum line
at reservoir and connect a hand-operated vacuum
pump to reservoir fitting. Apply vacuum. Reservoir
vacuum should not bleed off. If vacuum is being lost,
replace reservoir.
(5) Verify operation of one-way check valve and
check it for leaks.Certain models may be
equipped with 2 check-valves.
(a) Locate one-way check valve. The valve is
located in vacuum line between vacuum reservoir
and engine vacuum source. Disconnect vacuum
hoses (lines) at each end of valve.
(b) Connect a hand-operated vacuum pump to
reservoir end of check valve. Apply vacuum. Vac-
uum should not bleed off. If vacuum is being lost,
replace one-way check valve.
(c) Connect a hand-operated vacuum pump to
vacuum source end of check valve. Apply vacuum.
Vacuum should flow through valve. If vacuum is
not flowing, replace one-way check valve. Seal thefitting at opposite end of valve with a finger and
apply vacuum. If vacuum will not hold, diaphragm
within check valve has ruptured. Replace valve.
REMOVAL
The vacuum reservoir is located behind, and at the
outer end of the instrument panel (Fig. 8). To gain
access for testing or removal, remove glovebox assem-
bly. Also remove fuse box access cover panel at end of
instrument panel. On vehicles equipped with LHD
(Left Hand Drive), this fuse access panel is located at
right end of instrument panel. On vehicles equipped
with RHD (Right Hand Drive), this access panel is
located at left end of instrument panel.
(1) Remove glovebox assembly. Access to reservoir
vacuum line and fitting can now be made.
(2) Remove vacuum line at reservoir.
(3) Remove fuse access cover panel at end of
instrument panel.
(4) Through fuse access opening, remove 2 horizon-
tally mounted screws (Fig. 8).
(5) From bottom of instrument panel, remove 1
vertically mounted screw (Fig. 9).
(6) Remove reservoir from instrument panel.
Fig. 8 VACUUM RESERVOIR LOCATION
1 - VACUUM RESERVOIR
2 - HORIZONTAL MOUNTING SCREWS
3 - OUTBOARD END OF I.P.
KJSPEED CONTROL 8P - 7

WIRING
TABLE OF CONTENTS
page page
WIRING DIAGRAM INFORMATION...... 8Wa-01-1
COMPONENT INDEX................. 8Wa-02-1
POWER DISTRIBUTION.............. 8Wa-10-1
JUNCTION BLOCK................... 8Wa-12-1
GROUND DISTRIBUTION............. 8Wa-15-1
BUS COMMUNICATIONS............. 8Wa-18-1
CHARGING SYSTEM................. 8Wa-20-1
STARTING SYSTEM................. 8Wa-21-1
FUEL/IGNITION SYSTEM............. 8Wa-30-1
TRANSMISSION CONTROL SYSTEM.... 8Wa-31-1
VEHICLE SPEED CONTROL........... 8Wa-33-1
ANTILOCK BRAKES.................. 8Wa-35-1
VEHICLE THEFT SECURITY SYSTEM.... 8Wa-39-1
INSTRUMENT CLUSTER.............. 8Wa-40-1
HORN/CIGAR LIGHTER/POWER OUTLET . 8Wa-41-1
AIR CONDITIONING-HEATER.......... 8Wa-42-1
AIRBAG SYSTEM................... 8Wa-43-1
INTERIOR LIGHTING................. 8Wa-44-1BODY CONTROL MODULE............ 8Wa-45-1
AUDIO SYSTEM.................... 8Wa-47-1
REAR WINDOW DEFOGGER........... 8Wa-48-1
OVERHEAD CONSOLE................ 8Wa-49-1
FRONT LIGHTING................... 8Wa-50-1
REAR LIGHTING.................... 8Wa-51-1
TURN SIGNALS..................... 8Wa-52-1
WIPERS........................... 8Wa-53-1
TRAILER TOW...................... 8Wa-54-1
POWER WINDOWS.................. 8Wa-60-1
POWER DOOR LOCKS............... 8Wa-61-1
POWER MIRRORS.................. 8Wa-62-1
POWER SEAT...................... 8Wa-63-1
POWER SUNROOF.................. 8Wa-64-1
SPLICE INFORMATION............... 8Wa-70-1
CONNECTOR PIN-OUTS.............. 8Wa-80-1
CONNECTOR/GROUND/
SPLICE LOCATION................. 8Wa-91-1 KJWIRING
8Wa-1

8W-42 AIR CONDITIONING-HEATER
Component Page
A/C Compressor Clutch............. 8Wa-42-5, 7
A/C Compressor Clutch Relay........ 8Wa-42-5, 7
A/C High Pressure Switch............. 8Wa-42-6
A/C Low Pressure Switch........... 8Wa-42-3, 6
A/C Pressure Transducer............. 8Wa-42-5
A/C- Heater Control............... 8Wa-42-2, 4
Auto Shut Down Relay............... 8Wa-42-5
Blend Door Actuator................. 8Wa-42-2
Blower Motor................... 8Wa-42-3, 4, 6
Blower Motor Relay.............. 8Wa-42-3, 4, 6
Blower Motor Resistor Block....... 8Wa-42-3, 4, 6
Body Control Module................ 8Wa-42-4
Cabin Heater....................... 8Wa-42-7
Cabin Heater Relay.................. 8Wa-42-7
Defogger Relay..................... 8Wa-42-2
Engine Control Module............. 8Wa-42-6, 7
Fuel Heater Relay................. 8Wa-42-3, 6
Fuel Pump Relay................... 8Wa-42-5Component Page
Fuse 1.......................... 8Wa-42-3, 6
Fuse 15........................... 8Wa-42-5
Fuse 16........................... 8Wa-42-7
Fuse 19........................... 8Wa-42-6
Fuse 21......................... 8Wa-42-5, 7
Fuse 24........................... 8Wa-42-3
Fuse 25........................... 8Wa-42-2
Fuse 30........................... 8Wa-42-2
G101............................. 8Wa-42-5
G103........................... 8Wa-42-5, 7
G111 ........................... 8Wa-42-3, 6
G112 ........................... 8Wa-42-3, 6
G200............................. 8Wa-42-4
G202............................. 8Wa-42-2
Instrument Cluster.................. 8Wa-42-4
Junction Block.............. 8Wa-42-2, 3, 4, 5, 6
Power Distribution Center....... 8Wa-42-3, 5, 6, 7
Powertrain Control Module.......... 8Wa-42-3, 5
KJ8W-42 AIR CONDITIONING-HEATER8Wa-42-1

(6) Position the camshaft drive gear into the tim-
ing chain aligning the V6 mark between the two
marked chain links (Two links marked during remov-
al).
(7) Using Special Tool 8428 Camshaft Wrench,
rotate the camshaft until the camshaft sprocket
dowel is aligned with the slot in the camshaft
sprocket. Install the sprocket onto the camshaft.
CAUTION: Remove excess oil from camshaft
sprocket bolt. Failure to do so can cause bolt over-
torque resulting in bolt failure.
(8) Remove excess oil from camshaft sprocket bolt,
then install the camshaft sprocket retaining bolt and
hand tighten.
(9) Remove timing chain wedge special tool 8379.
(10) Using Special Tool 6958 spanner wrench with
adapter pins 8346, torque the camshaft sprocket
retaining bolt to 122 N´m (90 ft. lbs.).
(11) Install the camshaft position sensor.
(12) Install the cylinder head cover.
CYLINDER HEAD COVER(S)
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly, resonator assem-
bly and air inlet hose.
(3) Drain cooling system, below the level of the
heater hoses. Refer to COOLING SYSTEM.(4) Remove accessory drive belt.
(5) Remove air conditioning compressor retaining
bolts and move compressor to the left.
(6) Remove heater hoses.
(7) Disconnect injector and ignition coil connectors.
(8) Disconnect and remove positive crankcase ven-
tilation (PCV) hose.
(9) Remove oil fill tube.
(10) Un-clip injector and ignition coil harness and
move away from cylinder head cover.
(11) Remove right rear breather tube and filter
assembly.
(12) Remove cylinder head cover retaining bolts.
(13) Remove cylinder head cover.
INSTALLATION
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs).
(3) Install right rear breather tube and filter
assembly.
(4) Connect injector, ignition coil electrical connec-
tors and harness retaining clips.
(5) Install the oil fill tube.
(6) Install PCV hose.
(7) Install heater hoses.
(8) Install air conditioning compressor retaining
bolts.
(9) Install accessory drive belt
(10) Fill Cooling system
(11) Install air cleaner assembly, resonator assem-
bly and air inlet hose.
(12) Connect battery negative cable.
INTAKE/EXHAUST VALVES &
SEATS
STANDARD PROCEDURE - REFACING
NOTE: Valve seats that are worn or burned can be
reworked, provided that correct angle and seat
width are maintained. Otherwise the cylinder head
must be replaced.
Fig. 23 Camshaft Bearing Caps Tightening
Sequence
9 - 34 ENGINE - 3.7LKJ
CAMSHAFT(S) (Continued)

INTAKE MANIFOLD
DESCRIPTION
The intake manifold (Fig. 86) is made of a compos-
ite material and features 300 mm (11.811 in.) long
runners which maximizes low end torque. The intake
manifold uses single plane sealing which consist of
six individual press in place port gaskets to prevent
leaks. The throttle body attaches directly to the
intake manifold. Eight studs and two bolts are used
to fasten the intake to the head.
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water (Spray Bottle) at
the suspected leak area.
(3) If engine RPM'S change, the area of the sus-
pected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove resonator assembly and air inlet hose.
(3) Disconnect throttle and speed control cables.
(4) Disconnect electrical connectors for the follow-
ing components: Refer to FUEL SYSTEM for compo-
nent locations.
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
(5) Disconnect vapor purge hose, brake booster
hose, speed control servo hose, positive crankcase
ventilation (PCV) hose.
(6) Disconnect generator electrical connections.
(7) Disconnect air conditioning compressor electri-
cal connections.
(8) Disconnect left and right radio suppressor
straps.
(9) Disconnect and remove ignition coil towers.
(10) Remove top oil dipstick tube retaining bolt
and ground strap.
Fig. 85 Oil Pump and Primary Timing Chain
Tensioner Tightening Sequence
Fig. 86 INTAKE MANIFOLD
1 - THROTTLE BODY
2 - INTAKE MANIFOLD
3 - INTAKE PORT GASKETS
9 - 68 ENGINE - 3.7LKJ
OIL PUMP (Continued)