
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

SERVICE PROCEDURES
HORN REMOVE/INSTALL
XJ
(1) Raise and support the vehicle.
(2) Remove the front underbody splash shield.
(3) Remove horn mounting bolt and horn (Fig. 3).
(4) Remove wire from horn.
(5) Reverse removal procedures to install.
YJ
(1) Disconnect wire harness connector from the
horn (Fig. 4).
(2) Remove horn and bracket mounting bolt. Horn
and bracket are removed as an assembly.
(3) Reverse removal procedures to install.
HORN SWITCH REMOVE/INSTALL
WARNING: ON VEHICLES EQUIPPED WITH AN AIR-
BAG, REFER TO GROUP 8M - RESTRAINT SYS-
TEMS BEFORE ATTEMPTING STEERING WHEEL
COMPONENT DIAGNOSIS OR SERVICE. FAILURE
TO TAKE PROPER PRECAUTIONS COULD RESULT
IN ACCIDENTAL AIRBAG DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
XJ
(1) Disconnect negative cable from battery and iso-
late.
(2) Using a small screwdriver, remove plastic cover
plug from top outer surface of steering wheel hub
(Fig. 5). Exit vehicle and disarm airbag by reaching
through driver's side window and turning arming
screw counter-clockwise to its travel limit. This is
done using an 8mm socket and manual drive. DO
NOT USE POWER-DRIVEN TOOLS.
(3) From back side of steering wheel, remove 4
nuts attaching airbag module to steering wheel. This
is done using a 10mm socket and manual drive. DO
NOT USE POWER-DRIVEN TOOLS.
(4) Remove airbag module from steering wheel.
(5) To access horn switch retaining screws, pry out
trim cover buttons on back of steering wheel spokes
directly behind horn switches. Remove retaining
screws.
(6) Disconnect horn switch wires located in the
lower portion of steering wheel hub cavity and re-
move switches from steering wheel.
(7) Reverse removal procedures to install. Tighten
hardware as follows:
²airbag module nuts-9to11Nzm (80 to 100 in.
lbs.)
²airbag arming screw - not to exceed 1 to 1.5 Nzm
(10 to 15 in. lbs.).
YJ
(1) Disconnect negative cable from battery.
(2) Remove horn button by pulling straight up.
Fig. 3 Horn Mounting - XJ
Fig. 4 Horn Mounting - YJ
JHORNS 8G - 3

DIAGNOSIS - XJ
WINDSHIELD WIPER SYSTEM
(1) Remove in-line circuit breaker near fuseblock
module and turn ignition switch to ACCESSORY or
ON.
(a) Measure voltage at battery side of circuit
breaker cavity. Meter should read battery voltage.
If not OK, repair wiring from ignition switch.
(b) Measure resistance across circuit breaker ter-
minals. Meter should read zero ohms. If not OK,
replace failed circuit breaker.
(2) Unplug wiper motor side of wiring harness con-
nector (gray) from wiper (multi-function) switch side
of wiring harness connector (black), or from intermit-
tent wipe module (if equipped) at base of steering col-
umn. Turn ignition switch to ACCESSORY or ON.
(a) Measure voltage at unplugged wiper motor
side of wiring harness connector (gray) terminal D.
Meter should read battery voltage. If not OK, re-
pair wiring from circuit breaker.
(b) Turn ignition switch to OFF and measure re-
sistance from unplugged wiper motor side of wiring
harness connector (gray) terminal G to ground.
Meter should read zero ohms. If not OK, repair
wiring to ground.
(3) Leave ignition switch in OFF, and back probe
wiring harness connector at wiper motor (Fig. 1).
Measure resistance from terminal 4 of wiper motor
side of connector to ground. Meter should read zero
ohms. If not OK, repair wiring to ground.
(4) If equipped with intermittent wipe, replace the
intermittent wipe module with a known good unitand test wiper operation in all modes. If OK, replace
faulty intermittent wipe module. If not OK, re-install
original module and go to next step.
(5) To test the wiper/washer (multi-function)
switch, see Windshield Wiper/Washer Switch. If
switch tests OK, go to step 6. If not OK, replace
switch and go to step 7.
(6) To test the wiper (multi-function) switch cir-
cuits, turn ignition switch to ACCESSORY or ON.
Position the wiper switch as indicated in the tests be-
low, and back probe switch side of wiring harness
connector (black).
(a) Measure voltage at connector terminal E with
wiper switch in LOW, MIST and with washer
switch depressed. Meter should read battery volt-
age. If not OK, repair wiring to switch.
(b) Measure voltage at connector terminal C with
wiper switch in HIGH. Meter should read battery
voltage. If not OK, repair wiring to switch.
(c) With wiper switch in LOW or HIGH, measure
voltage at connector terminal F, then move wiper
switch to OFF. Meter should read battery voltage
until wipers park and then zero volts. If OK, go to
step 7. If not OK, check wiring to wiper motor, then
go to step 7.
(7) To test the wiper motor, turn the ignition
switch to ACCESSORY or ON. Position the wiper
(multi-function) switch and back probe the motor
connector (Fig. 1) as indicated.
(a) Wiper switch in any position, measure volt-
age at terminal 1. Meter should read battery volt-
age. If not OK, repair wiring from circuit breaker.
(b) Wiper switch in LOW, measure voltage at ter-
minal 5. Meter should read battery voltage. If OK,
but wipers do not operate, replace failed wiper mo-
tor. If not OK, repair wiring from switch or inter-
mittent wipe module connector.
(c) Wiper switch in HIGH, measure voltage at
terminal 6. Meter should read battery voltage. If
OK, but wipers do not operate, replace failed wiper
motor. If not OK, repair wiring from switch or in-
termittent wipe module connector.
(d) Wiper switch in LOW or HIGH, voltmeter
connected to terminal 2. Turn wiper switch to OFF
and observe meter. Meter should read battery volt-
age when switch goes to OFF, then zero volts after
wipers park. If battery voltage is present, but wip-
ers fail to park; or, if no battery voltage present, re-
place failed wiper motor.
Fig. 1 Windshield Wiper Motor Connector
JWIPER AND WASHER SYSTEMS - XJ 8K - 3

gate wiper switch terminal C. Meter should read
battery voltage. If not OK, replace switch.
(4) Remove liftgate cover and measure resistance
from liftgate wiper motor terminal 1 to a good
ground. Meter should read zero ohms. If not OK, re-
pair open to ground splice.
(5) Turn ignition switch to ACCESSORY and lift-
gate wiper switch to WASH. Measure voltage at mo-
tor connector terminals 2, 3 and 4. Meter should read
battery voltage. If OK, replace wiper motor. If not
OK, repair open(s) to liftgate wiper switch.
LIFTGATE WASHER SYSTEM
(1) Turn ignition switch to ACCESSORY and place
liftgate wiper/washer switch in WASH. Operate lift-
gate wiper motor. If motor does not operate check
fuse 1. Replace faulty fuse, if required.
(2) Turn ignition switch to ACCESSORY and un-
plug liftgate washer pump connector.
(a) Measure resistance at pump connector termi-
nal B (ignition switch OFF). Meter should read
zero ohms. If not OK, repair open to ground.
(b) Measure voltage at pump connector terminal
A, switch in WASH. Meter should read battery
voltage. If OK, replace pump. If not OK, go to step
3.
(3) Remove switch and reconnect below instrument
panel. Backprobe switch connector with ignition
switch in ACCESSORY.
(a) Measure voltage at switch connector terminal
B. Meter should read battery voltage. If not OK, re-
pair open to fuse.
(b) Measure voltage at switch connector terminal
A, switch in WASH. Meter should read battery
voltage. If not OK, replace switch.
LIFTGATE WIPER/WASHER SWITCH
Use an ohmmeter to test switch resistance as
shown in the following charts. If switch fails to per-form as shown, replace faulty switch.
JWIPER AND WASHER SYSTEMS - XJ 8K - 5

DIAGNOSIS - YJ
WINDSHIELD WIPER SYSTEM
(1) Remove circuit breaker from fuseblock module
and turn ignition switch to ACCESSORY or ON.
(a) Measure voltage at battery side of circuit
breaker cavity. Meter should read battery voltage.
If not OK, repair wiring from ignition switch.
(b) Measure resistance across circuit breaker ter-
minals. Meter should read zero ohms. If not OK,
replace failed circuit breaker.
(2) Unplug wiper motor side of wiring harness con-
nector (gray) from wiper switch side of wiring har-
ness connector (black), or from intermittent wipe
module (if equipped) at base of steering column. Turn
ignition switch to ACCESSORY or ON.
(a) Measure voltage at unplugged wiper motor
side of wiring harness connector (gray) terminal D.
Meter should read battery voltage. If not OK, re-
pair wiring from circuit breaker.
(b) Turn ignition switch to OFF and measure re-
sistance from unplugged wiper motor side of wiring
harness connector (gray) terminal G to ground.
Meter should read zero ohms. If not OK, repair
wiring to ground.
(3) Leave ignition switch in OFF, and back probe
wiring harness connector at wiper motor. Measure re-
sistance from terminal E of wiper motor side of con-
nector to ground. Meter should read zero ohms. If not
OK, repair wiring to ground.
(4) If equipped with intermittent wipe, turn igni-
tion switch to ACCESSORY or ON. Turn wiper
switch to LOW or HIGH. Unplug wiper switch side of
wiring harness connector (black) from intermittent
wipe module. Then plug both connectors that have
been removed from intermittent wipe module into
each other.
CAUTION: DO NOT move the wiper switch to DE-
LAY with the intermittent wipe module removed
from the circuit. If the switch is moved to the DE-
LAY position during the next step, the switch will be
damaged.
Test wiper operation in LOW and HIGH speed
modes, and test washer operation. If these modes
were inoperative, but are OK now, replace failed in-
termittent wipe module.
(5) To test the wiper/washer switch, see Windshield
Wiper/Washer Switch Testing. Turn ignition switch to
OFF. Position the wiper switch as indicated, and
back probe wiper switch side of wiring harness con-
nector (black). If switch tests OK, go to step 6. If not
OK, replace switch and go to step 7.
(6) To further test the wiper/washer switch, turn
ignition switch to ACCESSORY or ON. Position thewiper switch as indicated in the tests below, and
back probe wiper switch side of wiring harness con-
nector (black).
(a) Measure voltage at connector terminal E with
wiper switch in LOW, MIST and with washer
switch depressed. Meter should read battery volt-
age. If not OK, replace switch.
(b) Measure voltage at connector terminal C with
wiper switch in HIGH. Meter should read battery
voltage. If not OK, replace switch.
(c) With wiper switch in LOW or HIGH, measure
voltage at connector terminal F, then move wiper
switch to OFF. Meter should read battery voltage
until wipers park and then zero volts. If OK, go to
step 7. If not OK, check wiring to wiper motor, then
go to step 8.
(7) To test the wiper motor, turn the ignition
switch to ACCESSORY or ON. Position the wiper
switch and back probe the motor connector as indi-
cated.
(a) Wiper switch in any position, measure volt-
age at terminal B. Meter should read battery volt-
age. If not OK, repair wiring from circuit breaker.
(b) Wiper switch in LOW, measure voltage at ter-
minal A. Meter should read battery voltage. If OK,
but wipers do not operate, replace failed wiper mo-
tor. If not OK, repair wiring from switch or inter-
mittent wipe module connector.
(c) Wiper switch in HIGH, measure voltage at
terminal H. Meter should read battery voltage. If
OK, but wipers do not operate, replace failed wiper
motor. If not OK, repair wiring from switch or in-
termittent wipe module connector.
(d) Wiper switch in LOW or HIGH, voltmeter
connected to terminal D. Turn wiper switch to OFF
and observe meter. Meter should read battery volt-
age when switch goes to OFF, then zero volts after
wipers park. If battery voltage is present, but wip-
ers fail to park; or, if no battery voltage present, re-
place failed wiper motor.
WINDSHIELD WASHER SYSTEM
WITH NON-INTERMITTENT WIPE
(1) Measure resistance from washer pump connec-
tor terminal B to a clean chassis ground. Meter
should read zero ohms. If not OK, repair open be-
tween terminal B and ground.
(2) Turn ignition switch to ON and press washer
switch.
(a) Measure voltage at switch connector terminal
B. Meter should read battery voltage. If not OK, re-
place wiper/washer switch.
(b) Measure voltage at washer pump connector
terminal A. Meter should read battery voltage. If
8K - 12 WIPER AND WASHER SYSTEMS - YJJ

(30) Remove key warning buzzer switch and re-
taining clip with a paper clip inserted below retainer
so that retainer is flattened (Fig. 24).
Do not attempt to remove buzzer switch and
clip separately. The clip could fall into the column
jacket.
(31) Remove ignition lock cylinder retaining screw
and pull lock cylinder out of column housing (Fig. 25)(32) Remove screws that attach housing and
shroud assembly to column jacket and carefully re-
move housing and shroud assembly (Fig. 26).
DO NOT let dimmer switch rod, lock pin or
lock rack fall out.
(33) Remove turn/hazard/wiper lever by pulling it
straight out of column.
(34) Remove wiper switch cover from back of hous-
ing and shroud assembly (Fig. 27). If equipped with
column shift, remove screw holding the cover on.
(35) Remove pivot screw from housing and remove
wiper switch.
Fig. 24 Buzzer Switch Remove
Fig. 25 Lock Cylinder Remove/Install
Fig. 26 Steering Column Housing Remove/Install
Fig. 27 Remove Pivot Screw
JWIPER AND WASHER SYSTEMS - YJ 8K - 23

(2) Remove the washer hose from the back of the
washer nozzle.(3) Remove the nut holding the nozzle to the glass.
(4) Install the new washer nozzle.
Fig. 31 Liftgate Washer Pump
JWIPER AND WASHER SYSTEMS - YJ 8K - 25

SERVICE PROCEDURES
INDEX
page page
Back-Up/Rear Turn Signal/Tail Lamp Bulb
ReplacementÐXJ....................... 12
Center High Mounted Stop Lamp (CHMSL)ÐXJ . . 12
Daytime Running Lights (Canada Only)ÐXJ..... 15
Drl Module ReplacementÐXJ................ 15
Fog Lamp ReplacementÐXJ.................. 9
Fog Lamp Switch ReplacementÐXJ........... 10
Fog LampsÐXJ........................... 7
Front Park/Turn Signal Lamp Bulb
ReplacementÐXJ........................ 9
Headlamp Alignment PreparationÐXJ........... 6
Headlamp AlignmentÐXJ.................... 6
Headlamp Bulb ReplacementÐXJ.............. 7Headlamp Delay Function Trouble DiagnosisÐXJ . 14
Headlamp Delay Module ReplacementÐXJ...... 14
Headlamp SwitchÐXJ...................... 10
Headlamp/Fog Lamp Adjustment Using Alignment
ScreenÐXJ............................. 7
License Plate LampÐXJ.................... 12
Multi-Function Switch Service ProceduresÐXJ.... 11
Sentinel Headlamp Delay ModuleÐXJ.......... 14
Side Marker Lamp Bulb ReplacementÐXJ....... 10
Underhood Lamp Bulb ReplacementÐXJ....... 13
Underhood Lamp ReplacementÐXJ........... 13
Underhood Lamp Service InformationÐXJ....... 12
HEADLAMP ALIGNMENTÐXJ
Headlamps can be aligned using the screen method
provided in this section. Alignment Tool C4466-A or
equivalent can also be used. Refer to instructions
provided with the tool for proper procedures.The
preferred headlamp alignment setting is 0 for
the left/right adjustment and 1(down for the
up/down adjustment.
HEADLAMP ALIGNMENT PREPARATIONÐXJ
(1) Verify headlamp dimmer switch and high beam
indicator operation.
(2) Correct defective components that could hinder
proper headlamp alignment.
(3) Verify proper tire inflation.
(4) Clean headlamp lenses.
(5) Verify that luggage area is not heavily loaded.
Fig. 1 Headlamp Alignment ScreenÐTypical
8L - 6 LAMPSÐXJ VEHICLESJ