1995 JEEP YJ battery

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

SPECIFICATIONS
BATTERY SPECIFICATIONS
STARTER SPECIFICATIONS
GENERATOR SPECIFICATIONS
TORQUE
TORQUEÐ2.5L
TORQUEÐ4.0L
TORQUE
8B - 8 BATTERY/STARTER/GENERATOR SERVICEJ

IGNITION SYSTEMS
CONTENTS
page page
COMPONENT IDENTIFICATION/SYSTEM
OPERATION........................... 1
COMPONENT REMOVAL/INSTALLATION...... 17
DIAGNOSTICS/SERVICE PROCEDURES....... 6IGNITION SWITCHÐXJ MODELS........... 26
IGNITION SWITCHÐYJ MODELS........... 29
SPECIFICATIONS........................ 32
COMPONENT IDENTIFICATION/SYSTEM OPERATION
INDEX
page page
Automatic Shutdown (ASD) Relay.............. 1
Camshaft Position Sensor.................... 2
Crankshaft Position Sensor................... 3
Distributors............................... 4
Engine Coolant Temperature Sensor............ 5
General Information........................ 1Ignition Coil.............................. 4
Intake Manifold Air Temperature Sensor.......... 5
Manifold Absolute Pressure (MAP) Sensor........ 5
Oxygen (O2S) Sensor....................... 5
Powertrain Control Module (PCM).............. 5
Throttle Position Sensor..................... 5
GENERAL INFORMATION
Throughout this group, references are made to par-
ticular vehicle models by alphabetical designation
(XJ or YJ) or by the particular vehicle nameplate. A
chart showing a breakdown of alphabetical designa-
tions is included in the Introduction group at the be-
ginning of this manual.
This section of the group, Component Identifica-
tion/System Operation, will discuss ignition system
operation and will identify ignition system compo-
nents.
For diagnostic procedures and adjustments, refer to
the Diagnostics/Service Procedures section of this
group.
For removal and installation of ignition system
components, refer to the Component Removal/Instal-
lation section of this group.
For other useful information, refer to On-Board Di-
agnostics in the General Diagnosis sections of Group
14, Fuel System in this manual.
For operation of the DRB Scan Tool, refer to the
appropriate Powertrain Diagnostic Procedures ser-
vice manual.
An Ignition specifications section is included at the
end of this group. A general Maintenance Schedule
(mileage intervals) for ignition related items can be
found in Group 0, Lubrication and Maintenance. This
schedule can also be found in the Owners Manual.
IGNITION SYSTEMS
A multi-port, fuel injected engine is used on all
models. The ignition system is controlled by the pow-
ertrain control module (PCM) on all engines. The
PCM was formerly referred to as the SBEC or engine
controller.
The ignition system consists of:
²Spark plugs
²Ignition coil
²Secondary ignition cables
²Distributor (contains rotor and camshaft position
sensor)
²Powertrain control module (PCM)
²Crankshaft position sensor
AUTOMATIC SHUTDOWN (ASD) RELAY
The automatic shutdown (ASD) relay is located in
the power distribution center (PDC) near the battery
(Fig. 1 or 2). As one of its functions, it will supply
battery voltage to the ignition coil.
The ground circuit for the ASD relay is controlled
by the powertrain control module (PCM). This is
done through pin/cavity number 51 of the PCM 60-
way connector. The PCM then regulates ASD relay
operation by switching this ground circuit on-and-off.
Also refer to Ignition Coil for additional informa-
tion.
JIGNITION SYSTEMS 8D - 1