1995 JEEP YJ service

(5) Connect positive lead of a test voltmeter (range
0-18 volts minimum) to generator battery output ter-
minal.
(6) Connect negative lead of test voltmeter to a
good ground.
(7) Connect an engine tachometer, then connect
battery negative cable to battery.
(8) Connect a variable carbon pile rheostat be-
tween battery terminals. Be sure carbon pile is in
OPEN or OFF position before connecting leads. See
Load Test in this group for instructions.
(9) Connect one end of a jumper wire to ground
and with other end probe green K20 field wire at
back of generator (Fig. 3). This will generate a DTC.
CAUTION: Do not connect green/orange A142 field
wire to ground. Refer to Group 8W - Wiring Dia-
grams for more information.TEST
(1) Start engine. Immediately after starting, re-
duce engine speed to idle.
(2) Adjust carbon pile and engine speed in incre-
ments until a speed of 1250 rpm and voltmeter read-
ing of 15 volts is obtained.
CAUTION: Do not allow voltage meter to read above
16 volts.
(3) The ammeter reading must be within limits
shown in Generator Output Voltage Specifications.
RESULTS
(1) If reading is less than specified and generator
output wire resistance is not excessive, generator
should be replaced. Refer to Group 8B - Battery/
Starter/Generator Service.
CHARGING SYSTEM DIAGNOSIS
JBATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 19

BATTERY/STARTER/GENERATOR SERVICE
CONTENTS
page page
BATTERY............................... 1
GENERATOR............................ 6SPECIFICATIONS......................... 8
STARTER AND STARTER RELAY............. 4
GENERAL INFORMATION
Group 8B covers battery, starter and generator ser-
vice procedures. For diagnosis of these components
and their related systems, refer to Group 8A - Bat-tery/Starting/Charging Systems Diagnostics. Refer to
Group 8W - Wiring Diagrams for complete circuit de-
scriptions and diagrams.
BATTERY
GENERAL INFORMATION
This section covers battery service procedures only.
For battery maintenance procedures, refer to Group 0
- Lubrication and Maintenance. While battery charg-
ing can be considered a service or maintenance pro-
cedure, this information is located in Group 8A -
Battery/Starting/Charging Systems Diagnostics. This
was done because the battery must be fully charged
before any diagnosis is performed.
It is important that the battery, starting, and
charging systems be thoroughly tested and inspected
any time a battery needs to be charged or replaced.
The cause of abnormal discharge, over-charging, or
premature failure of the battery must be diagnosed
and corrected before a battery is replaced or returned
to service. Refer to Group 8A - Battery/Starting/
Charging Systems Diagnostics.
The factory installed low-maintenance battery (Fig.
1) has removable battery cell caps. Water can be
added to this battery. The battery is not sealed and
has vent holes in the cell caps. The chemical compo-
sition within the low-maintenance battery reduces
battery gassing and water loss at normal charge and
discharge rates. Therefore, the battery should not re-
quire additional water in normal service.
However, low electrolyte can be caused by an over-
charging condition. Be certain to diagnose charging
system before returning vehicle to service. Refer to
Group 8A - Battery/Starting/Charging Systems Diag-
nostics for more information.
BATTERY REMOVE/INSTALL
(1) Turn ignition switch to OFF position. Make
sure all electrical accessories are off.
(2) Loosen the cable terminal clamps and remove
both battery cables, negative cable first. If necessary,
use a puller to remove terminal clamps from battery
posts (Fig. 2).
(3) Inspect the cable terminals for corrosion and
damage. Remove corrosion using a wire brush or post
Fig. 1 Low-Maintenance Battery
Fig. 2 Remove Battery Terminal Clamp
JBATTERY/STARTER/GENERATOR SERVICE 8B - 1

and terminal cleaning tool, and a sodium bicarbonate
(baking soda) and warm water cleaning solution (Fig.
3). Replace cables that have damaged or deformed
terminals.
WARNING: WEAR A SUITABLE PAIR OF RUBBER
GLOVES (NOT THE HOUSEHOLD TYPE) WHEN RE-
MOVING A BATTERY BY HAND. SAFETY GLASSES
SHOULD ALSO BE WORN. IF THE BATTERY IS
CRACKED OR LEAKING, THE ELECTROLYTE CAN
BURN THE SKIN AND EYES.
(4) Remove battery holddowns (Fig. 4 or 5) and re-
move battery from vehicle.(5) Inspect battery tray (Fig. 6 or 7) and hold-
downs for corrosion or damage. Remove corrosion us-
ing a wire brush and a sodium bicarbonate (baking
soda) and warm water cleaning solution. Paint any
exposed bare metal and replace any damaged parts.
(6) Inspect the battery case for cracks or other
damage that could result in electrolyte leaks. Also
check battery terminal posts for looseness. Batteries
with damaged cases or loose posts must be replaced.
(7) Check electrolyte level in the battery. Use a
putty knife or other suitable wide-bladed flat tool to
Fig. 3 Clean Battery Cable Terminal
Fig. 4 Battery HolddownÐXJ
Fig. 5 Battery HolddownÐYJ
Fig. 6 Battery TrayÐXJ
8B - 2 BATTERY/STARTER/GENERATOR SERVICEJ

pry cell caps off (Fig. 8). Do not use a screwdriver.
Add distilled water to each cell until the liquid
reaches the bottom of the vent well. DO NOT OVER-
FILL. If battery is discharged, charge as required.
Refer to Group 8A - Battery/Starting/Charging Sys-
tems Diagnosis for more information.
(8) If the battery is to be reinstalled, clean outside
of battery case and top cover with sodium bicarbon-
ate (baking soda) and warm water cleaning solution
(Fig. 9) to remove acid film. Flush with clean water.
Ensure that cleaning solution does not enter cells
through the vent holes. If the battery is being re-
placed, refer to Specifications in Group 8A - Battery/
Starting/Charging Systems Diagnostics to confirm
replacement has correct classification and ratings for
the vehicle.(9) Clean corrosion from battery posts (Fig. 10)
with a wire brush or post and terminal cleaner, and
sodium bicarbonate (baking soda) and warm water
cleaning solution.
(10) Position battery in tray. Ensure that positive
and negative posts are correctly positioned. The cable
terminals must reach the correct battery post with-
out stretching.
(11) Loosely install battery holddown hardware.
Ensure that battery base is correctly positioned in
tray, then tighten holddowns to 2.2 Nzm (20 in. lbs.)
torque.
Fig. 7 Battery TrayÐYJ
Fig. 8 Removing Cell Cap
Fig. 9 Clean Battery
Fig. 10 Clean Battery Post
JBATTERY/STARTER/GENERATOR SERVICE 8B - 3

CAUTION: Be certain that battery cables are con-
nected to the correct battery terminals. Reverse po-
larity can damage electrical components.
(12) Place oiled felt washer on battery positive ter-
minal post.
(13) Install and tighten battery positive cable ter-
minal clamp. Then install and tighten negative cableterminal clamp. Both cable clamp bolts require
torque of 8.5 Nzm (75 in. lbs.).
(14) Apply a thin coating of petroleum jelly or
chassis grease to cable terminals and battery posts.
STARTER AND STARTER RELAY
GENERAL INFORMATION
This section covers starter and starter relay service
procedures only. For diagnostic procedures, refer to
Group 8A - Battery/Starting/Charging Systems Diag-
nostics. Service procedures for other starting system
components can be found as follows:
²battery - see Battery, in this group
²ignition switch - refer to Group 8D - Ignition Sys-
tems
²park/neutral position switch (automatic transmis-
sion) - refer to Group 21 - Transmission and Transfer
Case
²wiring harness and connectors - refer to Group 8W
- Wiring Diagrams.
STARTER
The starter motor incorporates several features to
create a reliable, efficient, compact and lightweight
unit. A planetary gear system (intermediate trans-
mission) is used between the electric motor and pin-
ion gear. This feature makes it possible to reduce the
dimensions of the starter. At the same time, it allows
higher armature rotational speed and delivers in-
creased torque through the pinion gear to the fly-
wheel or drive plate ring gear.
The use of a permanent magnet field also reduces
starter size and weight. This field consists of six
high-strength permanent magnets. The magnets are
aligned according to their polarity and are perma-
nently fixed in the starter field frame.
The starter motors for all engines are activated by
a solenoid mounted to the overrunning clutch hous-
ing. However, the starter motor/solenoid are serviced
only as a complete assembly. If either component
fails, the entire assembly must be replaced.
This unit is highly sensitive to hammering, shocks
and external pressure.
CAUTION: The starter motor MUST NOT BE
CLAMPED in a vise by the starter field frame. Doing
so may damage the magnets. It may be clamped by
the mounting flange ONLY.CAUTION: Do not connect starter motor incorrectly
when tests are being performed. The permanent
magnets may be damaged and rendered unservice-
able.
STARTER RELAY
The starter relay is an International Standards Or-
ganization (ISO) type relay, and is located in the
Power Distribution Center (PDC). Refer to underside
of PDC cover for relay location.
STARTER REMOVE/INSTALLÐ2.5L
XJ MODELS
(1) Disconnect battery negative cable.
(2) Remove exhaust clamp from bracket (Fig. 11).
(3) Remove nut and bolt from forward end of brace
rod (automatic transmission only).
Fig. 11 Exhaust Clamp and Brace Remove (XJÐ
2.5L)
8B - 4 BATTERY/STARTER/GENERATOR SERVICEJ

(4) Remove nut from lower end of brace rod (auto-
matic transmission only).
(5) Remove brace rod and bracket (automatic
transmission only).
(6) Remove nut, bolt and bracket from bell housing
(manual transmission only).
(7) Disconnect battery cable and solenoid feed wire
from solenoid (Fig. 12).
(8) Remove starter mounting bolts, starter motor
and shims.
Shim thickness available is 0.381 mm (0.015
in.). Refer to 2.5L Starter Noise Diagnosis in
Group 8A - Battery/Starting/Charging Systems
Diagnostics for proper shim selection.
(9) Reverse removal procedures to install and
torque mounting hardware as shown in Specifica-
tions.
YJ MODELS
(1) Disconnect battery negative cable.
(2) Disconnect battery cable from solenoid battery
terminal (Fig. 13).
(3) Disconnect solenoid feed wire.
(4) Remove starter mounting bolts.
(5) Remove starter motor and shims.
Shim thickness available is 0.381 mm (0.015
in.). Refer to 2.5L Starter Noise Diagnosis in
Group 8A - Battery/Starting/Charging Systems
Diagnosis for proper shim selection.
(6) Reverse removal procedures to install and
torque mounting hardware as shown in Specifica-
tions.
STARTER REMOVE/INSTALLÐ4.0L
(1) Disconnect battery negative cable.
(2) Raise and support vehicle.(3) Disconnect battery cable and solenoid feed wire
from solenoid.
(4) Remove starter lower mounting bolt (Fig. 14).
(5) Remove starter upper mounting bolt and re-
move starter.
(6) Reverse removal procedures to install and
torque mounting hardware as shown in Specifica-
tions.
Fig. 12 Starter Remove/Install (XJÐ2.5L)
Fig. 13 Starter Remove/Install (YJÐ2.5L)
Fig. 14 Starter Remove/InstallÐ4.0L
JBATTERY/STARTER/GENERATOR SERVICE 8B - 5

STARTER RELAY REMOVE/INSTALL
(1) Disconnect battery negative cable.
(2) Remove starter relay by unplugging unit from
PDC (Fig. 15 or 16).(3) Install starter relay by aligning relay terminals
with cavities in PDC and plugging relay in.
(4) Connect negative cable to battery.
(5) Test relay operation.
GENERATOR
GENERAL INFORMATION
This section covers generator service procedures
only. For generator or charging system diagnosis, re-
fer to Group 8A - Battery/Starting/Charging Systems
Diagnostics.
The generator is belt-driven by the engine. All en-
gines use serpentine drive. The generator is serviced
only as a complete assembly. If the generator fails for
any reason, the entire assembly must be replaced.
Two generator output ratings are available, de-
pending upon optional equipment. Be certain that
the replacement generator has the same output rat-
ing as the original unit. Refer to Group 8A - Battery/
Starting/Charging Systems Diagnostics and see
Specifications.
The generator field control (voltage regulator) cir-
cuitry is internal to the Powertrain Control Module
(PCM). If faulty, the entire PCM must be replaced.
Refer to Group 14 - Fuel System for PCM service
procedure.
GENERATOR REMOVE/INSTALLÐLEFT-HAND
DRIVE
WARNING: DISCONNECT NEGATIVE CABLE FROM
BATTERY BEFORE REMOVING BATTERY OUTPUT
WIRE FROM GENERATOR. FAILURE TO DO SO
CAN RESULT IN INJURY.
ALL WITH 2.5L AND YJ WITH 4.0L
(1) Disconnect battery negative cable.
(2) Remove generator drive belt. Refer to Group 7 -
Cooling System for procedure.
(3) Remove generator battery output terminal nut,
2 field terminal nuts, ground and harness holddown
nuts (Fig. 17). Remove wire connector assembly.
(4) Remove 2 generator mounting bolts and remove
generator from vehicle.
(5) Reverse removal procedure to install. Torque
generator hardware as shown in Specifications.
CAUTION: Never force a belt over a pulley rim us-
ing a screwdriver. The synthetic fiber of the belt can
be damaged.
Fig. 15 Power Distribution CenterÐXJFig. 16 Power Distribution CenterÐYJ
8B - 6 BATTERY/STARTER/GENERATOR SERVICEJ

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 the belt routing label in engine
compartment, or refer to Belt Schematics in Group
7 - Cooling System.
XJ WITH 4.0L
(1) Disconnect battery negative cable.
(2) Remove generator drive belt. Refer to Group 7 -
Cooling System for procedure.
(3) Raise and support vehicle.
(4) Remove generator battery output terminal nut,
2 field terminal nuts, ground and harness holddown
nuts (Fig. 17). Remove wire connector assembly.
(5) Remove 2 generator mounting bolts and remove
generator from vehicle.
(6) Reverse removal procedure to install. Torque
generator hardware as shown in Specifications.
CAUTION: Never force a belt over a pulley rim us-
ing 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 ifthe belt is installed incorrectly, causing the engine
to overheat. Refer to the belt routing label in engine
compartment, or refer to Belt Schematics in Group
7 - Cooling System.
GENERATOR REMOVE/INSTALLÐRIGHT-HAND
DRIVE
WARNING: DISCONNECT NEGATIVE CABLE FROM
BATTERY BEFORE REMOVING BATTERY OUTPUT
WIRE FROM GENERATOR. FAILURE TO DO SO
CAN RESULT IN INJURY.
(1) Disconnect battery negative cable.
(2) Remove 2 screws holding electric cooling fan
(Fig. 18).
(3) Unplug electric cooling fan wiring connector
and pull fan unit up and out of vehicle.
(4) Remove generator drive belt. Refer to Group 7 -
Cooling System for procedure.
(5) Remove generator mounting bolts.
(6) Position generator to gain access to all of the
wire connectors. Remove generator battery output
terminal nut, 2 field terminal nuts, ground and har-
ness holddown nuts (Fig. 17). Remove wire connector
assembly.
(7) Remove generator from vehicle.
(8) Reverse removal procedure to install. Torque
generator hardware as shown in Specifications.
Fig. 17 Remove/Install Generator Connector
Fig. 18 Electric Cooling Fan Remove/Install
JBATTERY/STARTER/GENERATOR SERVICE 8B - 7