2002 JEEP LIBERTY Low power

INSTALLATION
Gasoline Powered Engines
(1) 2.4L Engine: Position generator to engine and
install 2 mounting bolts. Refer to torque specifica-
tions.
(2) 3.7L Engine: Position generator to engine and
install 3 mounting bolts. Tighten 2 horizontal mount-
ing bolts to specified torque. Tighten 1 verticle
mounting bolt to specified torque. Refer to torque
specifications.
(3) Snap field wire connector into rear of genera-
tor.
(4) Install B+ terminal and nut to generator
mounting stud. Refer to torque specifications.
(5) Snap plastic protective cover to B+ terminal.
CAUTION: Never force a belt over a pulley rim
using a screwdriver. The synthetic fiber of the belt
can be damaged.
CAUTION: When installing a serpentine accessory
drive belt, the belt MUST be routed correctly. The
water pump will be rotating in the wrong direction if
the belt is installed incorrectly, causing the engine
to overheat. Refer to belt routing label in engine
compartment, or refer to Belt Schematics in 7, Cool-
ing System.
(6) Install drive belt Refer to 7, Cooling System for
belt routing, belt adjustment and bolt tightening pro-
cedures.
(7) Install negative battery cable to battery.
GENERATOR DECOUPLER
PULLEY
DESCRIPTION
The generator decoupler is used only with
certain engines.The decoupler is used in place of
the standard generator drive pulley (Fig. 5).
Fig. 3 GENERATOR - 2.4L
1 - UPPER MOUNTING BOLT
2 - GENERTOR
3 - LOWER MOUNTING BOLT
Fig. 4 GENERATOR - 3.7L
1 - GENERATOR
2 - VERTICAL MOUNTING BOLT
3 - HORIZONTAL MOUNTING BOLTS
8F - 26 CHARGING SYSTEMKJ
GENERATOR (Continued)

VOLTAGE REGULATOR
DESCRIPTION
The Electronic Voltage Regulator (EVR) is not a
separate component. It is actually a voltage regulat-
ing circuit located within the Powertrain Control
Module (PCM). The EVR is not serviced separately. If
replacement is necessary, the PCM must be replaced.
OPERATION
The amount of DC current produced by the gener-
ator is controlled by EVR circuitry contained within
the Powertrain Control Module (PCM). This circuitry
is connected in series with the generators second
rotor field terminal and its ground.
Voltage is regulated by cycling the ground path to
control the strength of the rotor magnetic field. TheEVR circuitry monitors system line voltage (B+) and
battery temperature (refer to Battery Temperature
Sensor for more information). It then determines a
target charging voltage. If sensed battery voltage is
0.5 volts or lower than the target voltage, the PCM
grounds the field winding until sensed battery volt-
age is 0.5 volts above target voltage. A circuit in the
PCM cycles the ground side of the generator field up
to 100 times per second (100Hz), but has the capabil-
ity to ground the field control wire 100% of the time
(full field) to achieve the target voltage. If the charg-
ing rate cannot be monitored (limp-in), a duty cycle
of 25% is used by the PCM in order to have some
generator output. Also refer to Charging Operation
for additional information.
KJCHARGING SYSTEM 8F - 31

STARTING SYSTEM
TABLE OF CONTENTS
page page
STARTING SYSTEM
DESCRIPTION.........................32
OPERATION...........................32
DIAGNOSIS AND TESTING - STARTING
SYSTEM............................33
INSPECTION - STARTING SYSTEM.........37
SPECIFICATIONS
TORQUE - GAS POWERED.............38
STARTER MOTOR - GAS POWERED......39
STARTER MOTOR
DIAGNOSIS AND TESTING - STARTER
MOTOR .............................39REMOVAL.............................39
INSTALLATION.........................41
STARTER MOTOR RELAY
DESCRIPTION.........................41
OPERATION...........................42
DIAGNOSIS AND TESTING -
STARTER RELAY......................42
REMOVAL.............................43
INSTALLATION.........................43
STARTING SYSTEM
DESCRIPTION
The starting system consists of:
²Starter relay
²Starter motor (including an integral starter sole-
noid)
Other components to be considered as part of start-
ing system are:
²Battery
²Battery cables
²Ignition switch and key lock cylinder
²Clutch pedal position switch (manual transmis-
sion)
²Park/neutral position switch (automatic trans-
mission)
²Wire harnesses and connections.
The Battery, Starting, and Charging systems oper-
ate in conjunction with one another, and must be
tested as a complete system. For correct operation of
starting/charging systems, all components used in
these 3 systems must perform within specifications.
When attempting to diagnose any of these systems, it
is important that you keep their interdependency in
mind.
The diagnostic procedures used in each of these
groups include the most basic conventional diagnostic
methods, to the more sophisticated On-Board Diag-
nostics (OBD) built into the Powertrain Control Mod-
ule (PCM). Use of an induction-type milliampere
ammeter, volt/ohmmeter, battery charger, carbon pile
rheostat (load tester), and 12-volt test lamp may be
required.Certain starting system components are monitored
by the PCM and may produce a Diagnostic Trouble
Code (DTC). Refer to Emission Control. See Diagnos-
tic Trouble Codes for additional information and a
list of codes.
OPERATION
The starting system components form two separate
circuits. A high-amperage feed circuit that feeds the
starter motor between 150 and 350 amperes (700
amperes - diesel engine), and a low-amperage control
circuit that operates on less than 20 amperes. The
high-amperage feed circuit components include the
battery, the battery cables, the contact disc portion of
the starter solenoid, and the starter motor. The low-
amperage control circuit components include the igni-
tion switch, the clutch pedal position switch (manual
transmission), the park/neutral position switch (auto-
matic transmission), the starter relay, the electro-
magnetic windings of the starter solenoid, and the
connecting wire harness components.
If the vehicle is equipped with a manual transmis-
sion, it has a clutch pedal position switch installed in
series between the ignition switch and the coil bat-
tery terminal of the starter relay. This normally open
switch prevents the starter relay from being ener-
gized when the ignition switch is turned to the
momentary Start position, unless the clutch pedal is
depressed. This feature prevents starter motor oper-
ation while the clutch disc and the flywheel are
engaged. The starter relay coil ground terminal is
always grounded on vehicles with a manual trans-
mission.
8F - 32 STARTING SYSTEMKJ

TESTING
COLD CRANKING TEST
For complete starter wiring circuit diagrams, refer
to 8, Wiring Diagrams. The battery must be fully-
charged and load-tested before proceeding. Refer to
Batteryin 8, Battery.
(1) Connect volt-ampere tester to battery terminals
(Fig. 1). See instructions provided by manufacturer of
volt-ampere tester being used.Note: Certain diesel
equipped models use dual batteries. If equipped
with dual battery system, tester should be con-
nected to battery on left side of vehicle only.
Also, tester current reading must be taken from
positive battery cable lead that connects to
starter motor.
(2) Fully engage parking brake.
(3) If equipped with manual transmission, place
gearshift selector lever in Neutral position and block
clutch pedal in fully depressed position. If equipped
with automatic transmission, place gearshift selector
lever in Park position.
(4) Verify that all lamps and accessories are
turned off.
(5) To prevent a gasoline engine from starting,
remove Automatic ShutDown (ASD) relay. To prevent
a diesel engine from starting, remove Fuel Pump
Relay. These relays are located in Power Distribution
Center (PDC). Refer to label on PDC cover for relay
location.
WARNING: IF EQUIPPED WITH DIESEL ENGINE,
ATTEMPT TO START ENGINE A FEW TIMES
BEFORE PROCEEDING WITH FOLLOWING STEP.(6) Rotate and hold ignition switch in Start posi-
tion. Note cranking voltage and current (amperage)
draw readings shown on volt-ampere tester.
(a) If voltage reads below 9.6 volts, refer to
Starter Motorin Diagnosis and Testing. If starter
motor is OK, refer toEngine Diagnosisin 9,
Engine for further testing of engine. If starter
motor is not OK, replace faulty starter motor.
(b) If voltage reads above 9.6 volts and current
(amperage) draw reads below specifications, refer
toFeed Circuit Testin this section.
(c) If voltage reads 12.5 volts or greater and
starter motor does not turn, refer toControl Cir-
cuit Testingin this section.
(d) If voltage reads 12.5 volts or greater and
starter motor turns very slowly, refer toFeed Cir-
cuit Testin this section.
NOTE: A cold engine will increase starter current
(amperage) draw reading, and reduce battery volt-
age reading.
FEED CIRCUIT TEST
The starter feed circuit test (voltage drop method)
will determine if there is excessive resistance in
high-amperage feed circuit. For complete starter wir-
ing circuit diagrams, refer 8, Wiring Diagrams.
When performing these tests, it is important to
remember that voltage drop is giving an indication of
resistance between two points at which voltmeter
probes are attached.
Example:When testing resistance of positive bat-
tery cable, touch voltmeter leads to positive battery
cable clamp and cable connector at starter solenoid.
If you probe positive battery terminal post and cable
connector at starter solenoid, you are reading com-
bined voltage drop in positive battery cable clamp-to-
terminal post connection and positive battery cable.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing tests,
be certain that following procedures are accom-
plished:
²Battery is fully-charged and load-tested. Refer to
Batteryin 8, Battery.
²Fully engage parking brake.
²If equipped with manual transmission, place
gearshift selector lever in Neutral position and block
clutch pedal in fully depressed position. If equipped
with automatic transmission, place gearshift selector
lever in Park position.
²Verify that all lamps and accessories are turned
off.
²To prevent a gasoline engine from starting,
remove Automatic ShutDown (ASD) relay. To prevent
a diesel engine from starting, remove Fuel Pump
Relay. These relays are located in Power Distribution
Fig. 1 Volts-Amps Tester Connections - Typical
1 - POSITIVE CLAMP
2 - NEGATIVE CLAMP
3 - INDUCTION AMMETER CLAMP
KJSTARTING SYSTEM 8F - 35
STARTING SYSTEM (Continued)

STARTER MOTOR - GAS POWERED
Starter Motor and Solenoid
Manufacturer Mitsubishi
Engine Application 2.4L / 3.7L
Power Rating 1.4 Kilowatt (1.9 Horsepower)
Voltage12 Volts
** Number of Permanent Magnets 6
Number of Brushes 4
Drive Type Planetary Gear Reduction
Free Running Test Voltage 11.2 Volts
Free Running Test Maximum Amperage Draw 90 Amperes
Free Running Test Minimum Speed 2400 rpm
Solenoid Closing Maximum Voltage Required 7.8 Volts
* Cranking Amperage Draw Test 160 Amperes
*Test at operating temperature. Cold engine, tight (new) engine, or heavy oil will increase starter amperage draw.
**The starter is equipped with permanent magnets. Never strike the starter case to attempt to loosen a sticking/
stuck armature as permanent magnets may crack or break.
STARTER MOTOR
DIAGNOSIS AND TESTING - STARTER MOTOR
Correct starter motor operation can be confirmed
by performing the following free running bench test.
This test can only be performed with starter motor
removed from vehicle. Refer to Specifications for
starter motor specifications.
(1) Remove starter motor from vehicle. Refer to
Starter Motor Removal and Installation.
(2) Mount starter motor securely in a soft-jawed
bench vise. The vise jaws should be clamped on the
mounting flange of starter motor. Never clamp on
starter motor by field frame.
(3) Connect a suitable volt-ampere tester and a
12-volt battery to starter motor in series, and set
ammeter to 100 ampere scale. See instructions pro-
vided by manufacturer of volt-ampere tester being
used.
(4) Install jumper wire from solenoid terminal to
solenoid battery terminal. The starter motor should
operate. If starter motor fails to operate, replace
faulty starter motor assembly.
(5) Adjust carbon pile load of tester to obtain free
running test voltage. Refer to Specifications for
starter motor free running test voltage specifications.
(6) Note reading on ammeter and compare reading
to free running test maximum amperage draw. Refer
to Specifications for starter motor free running test
maximum amperage draw specifications.(7) If ammeter reading exceeds maximum amper-
age draw specification, replace faulty starter motor
assembly.
STARTER SOLENOID
This test can only be performed with starter motor
removed from vehicle.
(1) Remove starter motor from vehicle. Refer to
Starter Motor Removal and Installation.
(2) Disconnect wire from solenoid field coil termi-
nal.
(3) Check for continuity between solenoid terminal
and solenoid field coil terminal with a continuity
tester (Fig. 7). There should be continuity. If OK, go
to Step 4. If not OK, replace faulty starter motor
assembly.
(4) Check for continuity between solenoid terminal
and solenoid case (Fig. 8). There should be continuity.
If not OK, replace faulty starter motor assembly.
REMOVAL
2.4L 4±Cylinder
(1) Disconnect and isolate negative battery cable.
(2) Raise and support vehicle.
(3) Remove solenoid wire from solenoid terminal
(Fig. 11).
(4) Remove battery cable from stud on starter sole-
noid (Fig. 11).
(5) Remove 2 starter mounting bolts (Fig. 9) and
remove starter from vehicle.
KJSTARTING SYSTEM 8F - 39
STARTING SYSTEM (Continued)

INSTALLATION
2.4L 4±Cylinder
(1) Position starter into bellhousing and install 2
bolts. Refer to torque specifications.
(2) Install battery cable and nut to stud on starter
solenoid. Refer to torque specifications.
(3) Install solenoid wire connector to solenoid ter-
minal.
(4) Lower vehicle.
(5) Connect negative battery cable.
3.7L V-6
(1) Position front of starter towards rear of vehicle
with solenoid position rotated until it is located below
starter. Install starter by passing it between exhaust
pipe and transmission bellhousing.
(2) Position starter into bellhousing and install 2
bolts. Refer to torque specifications.
(3) Install battery cable and nut to stud on starter
solenoid. Refer to torque specifications.
(4) Install solenoid wire connector to solenoid ter-
minal.
(5) Position starter heat shield and install nut at
front of starter.
(6) Install 2 starter heat shield bolts at side of
starter.
(7) Install front propeller shaft.
(8) Install 2 flange bolts securing left exhaust
downpipe to crossover pipe.
(9) Lower vehicle.
(10) Connect negative battery cable.
STARTER MOTOR RELAY
DESCRIPTION
The starter relay is an electromechanical device
that switches battery current to the pull-in coil of the
starter solenoid when ignition switch is turned to
Start position. The starter relay is located in the
Power Distribution Center (PDC) in the engine com-
partment. See PDC cover for relay identification and
location.
The starter relay is a International Standards
Organization (ISO) relay. Relays conforming to ISO
specifications have common physical dimensions, cur-
rent capacities, terminal patterns, and terminal func-
tions.
The starter relay cannot be repaired or adjusted
and, if faulty or damaged, it must be replaced.
Fig. 11 STARTER ELECTRICAL CONNECTORS -
2.4L/3.7L
1 - BATERY CABLE NUT
2 - BATTERY CABLE
3 - SOLENOID CONNECTOR
4 - HEAT SHIELD
Fig. 12 STARTER - 3.7L
1-STARTER
2 - MOUNTING BOLTS (2)
KJSTARTING SYSTEM 8F - 41
STARTER MOTOR (Continued)

OPERATION
The ISO relay consists of an electromagnetic coil, a
resistor or diode, and three (two fixed and one mov-
able) electrical contacts. The movable (common feed)
relay contact is held against one of the fixed contacts
(normally closed) by spring pressure. When electro-
magnetic coil is energized, it draws the movable con-
tact away from normally closed fixed contact, and
holds it against the other (normally open) fixed con-
tact.
When electromagnetic coil is de-energized, spring
pressure returns movable contact to normally closed
position. The resistor or diode is connected in parallel
with electromagnetic coil within relay, and helps to
dissipate voltage spikes produced when coil is de-en-
ergized.
DIAGNOSIS AND TESTING - STARTER RELAY
The starter relay is located in the Power Distribu-
tion Center (PDC) in engine compartment. Refer to
label on PDC cover for relay location.
RELAY TEST
(1) Remove starter relay (Fig. 13) from PDC.
(2) A relay in de-energized position should have
continuity between terminals 87A and 30, and no
continuity between terminals 87 and 30. If OK, go to
Step 3. If not OK, replace faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   5 ohms. If OK, go to Step
4. If not OK, replace faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, perform following Relay Circuit Test.
If not OK, replace faulty relay.
RELAY CIRCUIT TEST
(1) The relay common feed terminal cavity (30) is
connected to battery voltage and should be hot at all
times. If OK, go to Step 2. If not OK, repair open cir-
cuit to fused B(+) fuse in PDC as required.
(2) The relay normally closed terminal (87A) is
connected to terminal 30 in de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) is con-
nected to common feed terminal (30) in energized
position. This terminal supplies battery voltage to
starter solenoid field coil. There should be continuity
between cavity for relay terminal 87 and starter sole-
noid terminal at all times. If OK, go to Step 4. If not
OK, repair open engine starter motor relay output
circuit to starter solenoid as required.
(4) The coil battery terminal (86) is connected to
electromagnet in relay. It is energized when ignition
switch is held in Start position. On vehicles with amanual transmission, the clutch pedal must be
blocked in fully depressed position for this test.
Check for battery voltage at cavity for relay terminal
86 with ignition switch in Start position, and no volt-
age when ignition switch is released to On position.
If OK, go to Step 5. If not OK with a manual trans-
mission, disconnect clutch pedal position switch wire
harness connector and install a jumper wire between
two cavities in body half of connector and check for
battery voltage again at cavity for relay terminal 86.
If now OK, replace faulty clutch pedal position
switch. If still not OK with a manual transmission or
if not OK with an automatic transmission, check for
open or shorted fused ignition switch output (start)
circuit to ignition switch and repair as required. If
fused ignition switch output (start) circuit is OK,
refer toIgnition Switch and Key Lock Cylinder.
(5) The coil ground terminal (85) is connected to
electromagnet in relay. On vehicles with manual
transmission, it is grounded at all times. On vehicles
with automatic transmission, it is grounded through
park/neutral position switch only when gearshift
selector lever is in Park or Neutral positions. Check
for continuity to ground at cavity for relay terminal
85. If not OK with a manual transmission, repair
open park/neutral position switch sense circuit to
ground as required. If not OK with an automatic
transmission, check for open or shorted park/neutral
position switch sense circuit to park/neutral position
switch and repair, as required. If park/neutral posi-
tion switch sense circuit checks OK, refer toPark/
Neutral Position Switch.
Fig. 13 STARTER RELAY (ISO MICRO RELAY)
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
8F - 42 STARTING SYSTEMKJ
STARTER MOTOR RELAY (Continued)

DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER SYSTEM
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information). The operation of
the electrically heated rear window defogger system
can be confirmed in one of the following manners:
²Turn the ignition switch to the run position.
²Set the defogger switch in the run position. The
rear window defogger operation can be checked by
feeling the rear window or outside rear view mirror
glass. A distinct difference in temperature between
the grid lines and the adjacent clear glass or the mir-
ror glass can be detected within three to four min-
utes of operation.
²Using a 12-volt DC voltmeter, contact the rear
glass heating grid terminal B (right side) with the
negative lead, and terminal A (left side) with the pos-
itive lead (Fig. 1). The voltmeter should read battery
voltage.
The above checks will confirm system operation.
Illumination of the defogger switch indicator lamp
means that there is electrical current available at the
output of the defogger relay, but does not confirmthat the electrical current is reaching the rear glass
heating grid lines.
If the defogger system does not operate, the prob-
lem should be isolated in the following manner:
(1) Confirm that the ignition switch is in the run
position.
(2) Ensure that the rear glass heating grid feed
and ground wires are connected to the glass. Confirm
that the ground wire has continuity to ground.
(3) Check the fuses in the Power Distribution Cen-
ter (PDC) and in the junction block. The fuses must
be tight in their receptacles and all electrical connec-
tions must be secure.
When the above steps have been completed and the
rear glass or outside rear view mirror heating grid is
still inoperative, one or more of the following is
faulty:
²Defogger switch
²Defogger relay
²HVAC control head circuitry
²Rear window grid lines (all grid lines would
have to be broken or one of the feed wires discon-
nected for the entire system to be inoperative)
²Outside rear view mirror heating grid.
If setting the defogger switch to the On position
produces a severe voltmeter deflection, check for a
short circuit between the defogger relay output and
the rear glass or outside rear view mirror heating
grids.
STANDARD PROCEDURE - REAR GLASS
HEATING GRID REPAIR
Repair of the rear glass heating grid lines, bus
bars, terminals or pigtail wires can be accomplished
using a Mopar Rear Window Defogger Repair Kit
(Part Number 4267922) or equivalent.
WARNING: MATERIALS CONTAINED IN THE REPAIR
KIT MAY CAUSE SKIN OR EYE IRRITATION. THE
KIT CONTAINS EPOXY RESIN AND AMINE TYPE
HARDENER, WHICH ARE HARMFUL IF SWAL-
LOWED. AVOID CONTACT WITH THE SKIN AND
EYES. FOR SKIN CONTACT, WASH THE AFFECTED
AREAS WITH SOAP AND WATER. FOR CONTACT
WITH THE EYES, FLUSH WITH PLENTY OF WATER.
DO NOT TAKE INTERNALLY. IF TAKEN INTER-
NALLY, INDUCE VOMITING AND CALL A PHYSICIAN
IMMEDIATELY. USE WITH ADEQUATE VENTILA-
TION. DO NOT USE NEAR FIRE OR FLAME. CON-
TAINS FLAMMABLE SOLVENTS. KEEP OUT OF THE
REACH OF CHILDREN.
(1) Mask the repair area so that the conductive
epoxy can be applied neatly. Extend the epoxy appli-
cation onto the grid line or the bus bar on each side
of the break (Fig. 2).
Fig. 1 REAR WINDOW DEFOGGER
1 - DEFOGGER BACKGLASS
2 - HEATED GLASS CONNECTOR9A9
3 - HINDGE MOUNTING SCREWS (2)
4 - HINDGE (LEFT SIDE)
5 - HINDGE MOUNTING SCREWS (2)
6 - HINDGE (RIGHT SIDE)
7 - HEATED GLASS CONNECTOR9B9
8 - BACKGLASS DEFOGGER GRID
8G - 4 WINDOW DEFOGGERKJ
WINDOW DEFOGGER (Continued)