1995 JEEP XJ audio

ELECTRICAL
GROUP INDEX
Group Group
AUDIO SYSTEMS........................ 8F
BATTERY/STARTER/GENERATOR SERVICE.... 8B
BATTERY/STARTING/CHARGING SYSTEMS
DIAGNOSTICS......................... 8A
CHIME/BUZZER WARNING SYSTEMS........ 8U
HORNS................................ 8G
IGNITION SYSTEMS...................... 8D
INSTRUMENT PANEL AND GAUGES......... 8E
LAMPS................................ 8L
OVERHEAD CONSOLE.................... 8C
POWER LOCKS.......................... 8P
POWER MIRRORS....................... 8TPOWER SEATS.......................... 8R
POWER WINDOWS....................... 8S
REAR WINDOW DEFOGGER............... 8N
RESTRAINT SYSTEMS................... 8M
TURN SIGNAL AND HAZARD WARNING
SYSTEMS............................. 8J
VEHICLE SPEED CONTROL SYSTEM......... 8H
WIPER AND WASHER SYSTEMS............ 8K
XJ WIRING DIAGRAMS-LEFT HAND DRIVE . . . 8W
XJ WIRING DIAGRAMS-RIGHT HAND DRIVE . 8W
YJ WIRING DIAGRAMS.................. 8W
BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS
CONTENTS
page page
BATTERY............................... 2
CHARGING SYSTEM..................... 17
IGNITION-OFF DRAW.................... 10SPECIFICATIONS........................ 23
STARTING SYSTEM...................... 11
USING ON-BOARD DIAGNOSTIC SYSTEM.... 22
GENERAL INFORMATION
The battery, starting, and charging systems operate
with one another; therefore, they must be tested as a
complete system. In order for the vehicle to start and
charge properly, all of the components involved in
these systems must perform within specifications.
Group 8A covers battery, starting (Fig. 1) and
charging (Fig. 2) system diagnostic procedures. These
procedures include the most basic conventional diag-
nostic methods, to On-Board Diagnostics (OBD) builtinto the Powertrain Control Module (PCM). Use of an
induction milliamp ammeter, volt/ohmmeter, battery
charger, carbon pile rheostat (load tester), and 12-
volt test lamp will be required.
All OBD-sensed systems are monitored by the
PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. See Us-
ing On-Board Diagnostic System in this group for
more information.
JELECTRICAL 8A - 1

AUDIO SYSTEMS
CONTENTS
page page
DIAGNOSIS............................. 2
GENERAL INFORMATION.................. 1SERVICE PROCEDURES................... 6
GENERAL INFORMATION
Following are general descriptions of major compo-
nents used in XJ (Cherokee)/YJ (Wrangler) audio sys-
tems. Refer to Group 8W - Wiring Diagrams for
complete circuit descriptions and diagrams.
RADIOS
Radio options for the XJ and YJ models include an
AM/FM stereo or an AM/FM stereo/cassette receiver.
Both units are Electronically-Tuned Radios (ETR)
and include a clock function. For more information
on radio features, setting procedures, and control
functions refer to the owner's manual.
IN-LINE FUSE
Each radio receives fused battery feed when the ig-
nition switch is in the ON or ACCESSORY position.
There is an additional in-line fuse in the back of the
radio chassis. The in-line fuse (Fig. 1) will blow to
protect the vehicle electrical system in the event of
internal radio failure.
IGNITION-OFF DRAW FUSE
All vehicles are equipped with an Ignition-Off
Draw (IOD) fuse that is removed when the vehicle is
shipped from the factory. This fuse feeds various ac-
cessories that require current when the ignition
switch is in the OFF position, including the clock and
radio station preset memory functions. The fuse is re-
moved to prevent battery discharge during vehicle
storage.The IOD fuse should be checked if the radio station
preset memory or clock functions are erratic or inop-
erative. The IOD fuse is located in the Power Distri-
bution Center (PDC). Refer to underside of PDC
cover for IOD fuse identification.
RADIO ILLUMINATION RELAY
All radios are connected to a radio illumination re-
lay. The relay controls the source of battery feed for
radio/clock display illumination.
When the park and headlamp switch is in the OFF
position, the radio illumination relay remains de-en-
ergized. The radio/clock display receives full battery
voltage through the normally closed contacts of the
relay. This results in the radio/clock display being il-
luminated at full brightness for easier visibility in
daylight.
When the park and headlamp switch is in the ON
position, the radio illumination relay coil is ener-
gized. With the relay coil energized, the normally
closed contacts of the relay open, and the normally
open contacts of the relay close. This causes the ra-
dio/clock display to receive battery feed through the
instrument panel dimmer switch. The display illumi-
nation brightness can now be adjusted with other
panel lamps for night visibility.
SPEAKERS
Speaker system options include two, four or six (XJ
only) speaker locations. On XJ model two-speaker
systems, one speaker is located in each front door.
Four-speaker systems add one speaker at each end of
a rear-mounted overhead sound bar. The premium
six-speaker option upgrades all the speakers in the
above locations, and adds one tweeter at each end of
the lower instrument panel.
On YJ model two-speaker systems, one speaker is
located at each end of the instrument panel. Four-
speaker systems add one speaker at each end of a
rear-mounted overhead sound bar.
Fig. 1 In-Line Fuse
JAUDIO SYSTEMS 8F - 1

ANTENNA
All models use a fixed-length stainless steel rod-
type antenna mast, installed at the right front (fend-
er on XJ, cowl side on YJ) of the vehicle. The
antenna mast is connected to the center wire of the
coaxial antenna cable and is not grounded to any
part of the vehicle.
To eliminate static, the antenna base must have a
good ground. The coaxial antenna cable shield (the
outer wire mesh of the cable) is grounded to the an-
tenna base and the radio chassis.
The factory installed ETRs automatically compen-
sate for radio antenna trim. Therefore, no antenna
trimmer adjustment is required or possible when re-
placing the receiver or the antenna.
RADIO NOISE SUPPRESSION
Radio Frequency Interference (RFI) and Electro-
Magnetic Interference (EMI) noise suppression is ac-
complished primarily through circuitry internal to
the radio receivers. These internal suppression de-
vices are only serviced as a part of the radio receiver.External suppression devices that are serviceable
and should be checked in the case of RFI or EMI
noise complaints include the following:
²radio antenna base ground
²engine-to-body ground strap
²resistor-type spark plugs
²radio suppression-type secondary ignition wiring.
In addition, if the source of RFI or EMI noise is
identified as a component on the vehicle (i.e.:genera-
tor, blower motor, etc.), the ground path for that com-
ponent should be checked. If excessive resistance is
found in that circuit, repair as required before con-
sidering any component replacement.
Fleet vehicles are available with an extra-cost RFI-
suppressed Powertrain Control Module (PCM). This
unit reduces interference generated by the PCM on
some radio frequencies used in two-way radio com-
munications. However, this unit will not resolve com-
plaints of RFI in the commercial AM or FM radio
frequency ranges.
DIAGNOSIS
RADIO
CAUTION: Do not operate the radio with speaker
leads detached since damage to the transistors
may result.
(1) Check fuse 2 in fuseblock module and fuse in
back of radio chassis. If OK, go to next step. If not
OK, replace fuse.
(2) Turn ignition switch to ON position. Check for
battery voltage at fuse 2. If OK, go to next step. If
not OK, repair circuit to ignition switch as required.
(3) Turn ignition switch to OFF position. Discon-
nect battery negative cable. Remove instrument clus-
ter bezel. Remove radio, but do not unplug any
connections. Check for continuity between the radio
chassis and a good ground. There should be continu-
ity. If OK, go to next step. If not OK, repair radio
ground circuit as required.
(4) Connect battery negative cable. Turn ignition
switch to ON position. See Radio Connections chart.
Check for battery voltage at cavity 3 of radio connec-
tor. If OK, go to next step. If not OK, repair circuit to
fuse 2 as required.
(5) Turn ignition switch to OFF position. Check for
battery voltage at cavity 4 of radio connector. If OK,
replace radio. If not OK, repair circuit to IOD fuse in
PDC as required.
SPEAKERS
CAUTION: Do not operate the radio with speaker
leads detached since damage to the transistors
may result.
(1) Turn radio on and adjust balance and fader
controls to check performance of each individual
speaker. Note the speaker locations that are not per-
forming correctly. Go to next step.
(2) Turn radio off. Disconnect battery negative ca-
ble. Remove instrument cluster bezel and remove ra-
dio. See Radio Connections chart. Check both the
speaker feed and return cavities at radio for continu-
ity to a good ground. There should be no continuity.
If OK, go to next step. If not OK, repair wiring cir-
cuit as required.
(3) Check resistance between speaker feed and re-
turn cavities. Meter should read between 3 and 8
ohms (speaker impedance). If OK, see diagnosis for
Radio. If not OK, go to next step.
(4) Unplug speaker wiring connector. Check for
continuity between speaker feed cavity at radio and
at speaker. Repeat check between speaker return
cavity at radio and at speaker. If OK, replace
speaker. If not OK, repair wiring circuit as required.
8F - 2 AUDIO SYSTEMSJ

RADIO DIAGNOSIS
JAUDIO SYSTEMS 8F - 3

RADIO ILLUMINATION RELAY
If the relay fails any one of Relay Tests, it is faulty
and should be replaced. If the relay passes the Relay
Tests, proceed to the Relay Circuit Tests.
On XJ models, the radio illumination relay is lo-
cated in the relay center (Fig. 2), which is fastened to
the lower instrument panel reinforcement behind the
lower instrument panel near the steering column. On
YJ models, the relay is taped to the instrument panel
wiring harness above and to the right of the radio,
near the glove box.
RELAY TESTS
Remove relay to perform the following tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30.(2) Resistance value between terminals 85 and 86
(electromagnet) is 7565 ohms.
(3) 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.
RELAY CIRCUIT TESTS
With relay still removed, perform the following
tests:
(1) The common feed terminal (30) is connected to
the radio display feed circuit. There should be conti-
nuity between cavity for relay terminal 30 and clock/
radio display feed cavity of radio connector at all
times. If not, repair circuit as required.
(2) The normally closed terminal (87A) is connected
to terminal 30 in the de-energized position. This circuit
provides ignition-switched battery voltage to the radio
display when the headlamp switch is off. There should
be battery voltage present at cavity for relay terminal
87A with the ignition switch in the ON position. If not,
repair circuit to ignition switch as required.
(3) The normally open terminal (87) is connected to
terminal 30 in the energized position. This circuit
provides instrument panel dimmer controlled feed to
the radio display when the headlamp switch is on.
There should be voltage present at cavity for relay
terminal 87 when the headlamp switch is on. Also,
the voltage reading should vary as the panel dimmer
switch is rotated. If not, repair circuit or panel dim-
mer switch as required.
(4) The coil battery terminal (86) connected to the
electromagnet in the relay. Check as follows:
(a) On YJ models, it is energized when the head-
lamp switch is on. There should be battery voltage at
cavity for relay terminal 86 with the headlamp switch
on. If not, repair circuit to headlamp switch as re-
quired.
(b) On XJ models, it is grounded at all times.
There should be continuity to ground at cavity for
relay terminal 86 at all times. If not, repair circuit
to ground as required.
RADIO CONNECTIONS
Fig. 2 Radio Illumination Relay - XJ
RADIO ILLUMINATION RELAY CONNECTIONS
8F - 4 AUDIO SYSTEMSJ

(5) The coil ground terminal (85) is connected to
the electromagnet in the relay. Check as follows:
(a) On YJ models, it is grounded at all times.
There should be continuity to ground at cavity for
relay terminal 85 at all times. If not, repair circuit
to ground as required.
(b) On XJ models, it is energized when the head-
lamp switch is on. There should be battery voltage
at cavity for relay terminal 85 with the headlamp
switch on. If not, repair circuit to headlamp switch
as required.
ANTENNA
The following four tests are used to diagnose the
antenna with an ohmmeter:
²mast to ground test (Test 1)
²tip-of-mast to tip-of-conductor test (Test 2)
²body ground to battery ground test (Test 3)
²body ground to coaxial shield test (Test 4).
Ohmmeter test lead connections for each test are
shown in Figure 3.
TEST 1
Test 1 determines if the antenna mast is insulated
from the base. Proceed as follows:
(1) Disconnect antenna cable lead from radio chas-
sis and isolate.
(2) Connect one ohmmeter lead to tip of antenna
mast and the other lead to the antenna base. Check
for continuity.
(3) There should be no continuity. If continuity is
found, replace defective or damaged antenna base
and cable assembly.
TEST 2
Test 2 checks the antenna for an open circuit as fol-
lows:
(1) Disconnect the antenna cable lead from the ra-
dio chassis.
(2) Connect one ohmmeter test lead to tip of an-
tenna mast. Connect remaining lead to tip of an-
tenna cable lead (the part inserted into the radio).
(3) Continuity should exist (ohmmeter should only
register a fraction of an ohm). High or infinite resis-
tance indicates damage to the base and cable assem-
bly. Replace if required.
TEST 3
Test 3 checks condition of the vehicle body ground
connection as follows:
(1) Connect one ohmmeter test lead to the vehicle
fender and the other lead to the battery negative
post.
(2) Resistance should be less than one ohm.
(3) If resistance is more than one ohm, check the
braided ground strap connected to the engine and ve-
hicle body for being loose, corroded, or damaged. Re-
pair as necessary.
TEST 4
Test 4 checks condition of the ground between the
antenna base and vehicle body as follows:
(1) Connect one ohmmeter test lead to the fender
and the other lead to the crimp on the coaxial an-
tenna cable shield.
(2) Resistance should be less then one ohm.
(3) If resistance is more then one ohm:
(a) On YJ models, replace the antenna base at-
taching screws with new cadmium plated screws.
(b) On XJ models, clean and/or tighten antenna
base to fender mounting hardware.
RADIO FREQUENCY INTERFERENCE
Inspect ground connections at:
²blower motor
²electric fuel pump
²generator
²ignition module
²wiper motor
²antenna coaxial ground
²radio ground
²body-to-engine ground strap (braided).
Clean, tighten or repair as required.
Also inspect the following secondary ignition sys-
tem components:
²spark plug wire routing and condition
²distributor cap and rotor
²ignition coil
²spark plugs.
Reroute spark plug wires or replace components as
required.
Fig. 3 Antenna Tests
JAUDIO SYSTEMS 8F - 5

SERVICE PROCEDURES
RADIO REMOVE/INSTALL - XJ
(1) Disconnect battery negative cable.
(2) Remove upper and lower steering column
shrouds and steering column to instrument panel be-
zel gap hider. If equipped with tilt steering, apply
tape to tilt mechanism on top of steering column to
protect instrument panel bezel from damage during
removal.
(3) Remove 4 instrument panel bezel attaching
screws (Fig. 4) and remove the bezel.
(4) Remove 2 radio attaching screws (Fig. 5).(5) Slide radio chassis out of instrument panel far
enough to disconnect radio electrical connector,
ground lead and antenna lead (Fig. 6). Remove radio
from instrument panel.
(6) To install radio, route harness above and to the
right of the radio cavity. Make radio harness, ground
and antenna connections.
(7) While installing the radio, make sure that clip
on top of radio (Fig. 7) is installed in mating slot of
instrument panel.
(8) Reverse removal procedures to complete instal-
lation.
SPEAKERS REMOVE/INSTALL - XJ
INSTRUMENT PANEL
(1) Remove parking brake retaining screw from
lower instrument panel (Fig. 8).
(2) Remove retaining screws and the lower instru-
ment panel (Fig. 9).
(3) Unplug wire harness connector.
(4) Remove speaker screws and speaker from lower
instrument panel (Fig. 10).
(5) Reverse removal procedures to install.
Fig. 4 Instrument Bezel Remove/Install - XJ
Fig. 5 Radio Mounting Screws Remove/Install - XJ
Fig. 6 Radio Wiring Remove/Install - XJ
Fig. 7 Radio Clip Install - XJ
8F - 6 AUDIO SYSTEMSJ

FRONT DOOR
(1) Remove interior door latch release assembly
and control panel retaining screws (Fig. 11).
(2) Disconnect control linkage and wire harness
connector.(3) Remove latch release and control panel assem-
bly.
(4) Remove armrest lower retaining screws.
(5) Swing armrest downward to a vertical position.
This is necessary to disconnect armrest from upper
retainer clip (Fig. 12).
(6) Pull armrest straight out from trim panel.
(7) Remove trim panel with a wide, flat-bladed tool
(Fig. 13).
To aid in removal of trim panel, start at the
bottom of the panel.
(8) Remove speaker attaching screws and discon-
nect speaker at wire harness.
(9) Reverse removal procedures to install.
SOUND BAR
(1) Disconnect battery negative cable.
Fig. 8 Parking Brake Remove/Install - XJ
Fig. 9 Lower Instrument Panel Remove/Install - XJ
Fig. 10 Instrument Panel Speaker Remove/Install -
XJ
Fig. 11 Control Panel Remove/Install - XJ
Fig. 12 Armrest Retainer Clip - XJ
JAUDIO SYSTEMS 8F - 7