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
(2) Carefully remove grille from speaker by placing
fingertips on outer circumference of grille and gently
prying straight down to disengage 4 mounting tabs.
(3) Drill out rivets securing speaker to sound bar.
(4) Lower speaker far enough to unplug wiring
from connector.
(5) Reverse removal procedures to install. Use new
rivets to secure speaker. Be certain that tabs on
speaker grille are inserted through slots in sound
bar.
SOUND BAR REMOVE/INSTALL - XJ
(1) Disconnect battery negative cable.
(2) Remove lens from cargo lamp housing.
(3) Remove screws securing left and right rear side
roof rail garnish moldings.
(4) Remove left and right rear side roof rail gar-
nish moldings.
(5) Remove 2 push-on retainers from pins inside
cargo lamp housing securing sound bar to rear roof
bow.
(6) Lower sound bar from roof area and remove
from vehicle.
(7) Reverse removal procedures to install. Use 2
new push-on retainers.
ANTENNA REMOVE/INSTALL - XJ
(1) Remove the fender inner splash panel mount-
ing nuts (Fig. 14) and move the panel aside to gain
access to the antenna base and cable.
The splash panel screws may be covered with
undercoating.
(2) Remove the antenna mast, nut and antenna
pad from the top of the fender (Fig. 15).
(3) Remove the passenger side kick panel.
(4) Disconnect the antenna lead (Fig. 16) by pull-
ing apart while twisting the metal connectors. DO
NOT PULL ON THE COAXIAL CABLE.
(5) Pull the rubber grommet out of the kick panel.(6) Remove the antenna assembly from inside the
wheel well.
(7) Reverse removal procedures to install.
(8) Verify antenna and radio operation.
Fig. 13 Trim Panel Remove - XJ
Fig. 14 Fender Inner Splash Panel Remove/Install -
XJ
Fig. 15 Nut and Antenna Pad Remove/Install - XJ
8F - 8 AUDIO SYSTEMSJ
HORNS
CONTENTS
page page
DIAGNOSIS............................. 2
GENERAL INFORMATION.................. 1SERVICE PROCEDURES................... 3
SPECIFICATIONS......................... 5
GENERAL INFORMATION
Following are general descriptions of the major
components in the XJ (Cherokee)/YJ (Wrangler) horn
systems. Refer to Group 8W - Wiring Diagrams for
complete circuit descriptions and diagrams.
HORN SWITCH
XJ
Two horn switches are installed in the steering
wheel, one on each side of the center-mounted driv-
er's airbag module. When either switch is depressed
it completes a circuit to ground for the coil side of the
horn relay. The steering wheel and steering column
must be properly grounded for the horn switches to
function. The horn switches are only serviced as a set
with their wiring. If either switch should fail, both
switches must be replaced.
YJ
A single switch is installed in the center of the
steering wheel, directly under the horn button. When
the horn button is depressed the switch completes a
circuit to ground for the coil side of the horn relay.
The steering wheel and steering column must be
properly grounded for the horn switch to function.
The horn switch is available for service.
HORN RELAY
On XJ models, the horn relay is a mini-relay in-
stalled in the relay center, which is mounted to the
lower instrument panel reinforcement inboard of thesteering column. On YJ models, the horn relay is a
ISO relay installed in the Power Distribution Center
(PDC) near the battery tray. Refer to underside of
PDC cover for relay identification.
One side of the horn relay electromagnetic coil re-
ceives battery voltage at all times. When a horn
switch is depressed, the other side of the relay coil is
grounded. The energized relay coil causes the nor-
mally open relay contacts to close, providing battery
voltage to the horn.
If a problem is encountered with a continuously
sounding horn, it can usually be quickly resolved by
removing the horn relay until further diagnosis is
completed.
HORNS
On YJ models, a standard single, low-note, dia-
phragm-type horn is mounted and grounded to the
left inner fender shield under the hood. Dual horns
are standard equipment on XJ models. The high-note
diaphragm-type horn is mounted and grounded to
the left radiator closure panel brace behind the front
bumper. The low-note diaphragm-type horn is con-
nected in parallel with the high-note horn and is
mounted and grounded to the right radiator closure
panel brace behind the front bumper.
On XJ models, a cadmium-plated screw is
used to attach the horns to the body. Do not
substitute other types of screws as they may be-
come corroded and cause a loss of ground.
JHORNS 8G - 1
DIAGNOSIS
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.
(1) Inspect fuses (F8 and F16 in PDC on YJ)(11 in
fuseblock module and F14 in PDC on XJ). Replace
fuses, as required.
(2) Remove the horn relay (in the PDC on YJ)(in
the relay center on XJ). See Horn Relay Connec-
tions-XJ (Fig. 1) or Horn Relay Connections-YJ (Fig.
2) and perform the following tests.
²The common feed terminal (30) is connected to
battery voltage and should be hot at all times. If bat-
tery voltage is not present at relay cavity 30, check
circuit to fuse (F16 on YJ)(11 on XJ). Repair as re-
quired.
²The normally closed terminal (87A) is connected to
terminal 30 in the de-energized position, but is not
used for this application.
²The normally open terminal (87) is connected to
the common feed terminal (30) in the energized posi-
tion. This terminal supplies battery voltage to the
horn. There should be continuity between relay cav-
ity 87 and the horn terminal at all times. If not, re-
pair wiring or connections as required.
²The coil battery terminal (86) is connected to the
electromagnet in the relay, and battery voltage
should be present at all times. If battery voltage is
not present at relay cavity 86, check circuit to fuse
(F16 on YJ)(11 on XJ). Repair as required.
²The coil ground terminal (85) is connected to the
electromagnet in the relay. It is grounded when the
horn switch is depressed. Check for continuity to
ground at relay cavity 85 with the horn switch de-
pressed. If no continuity is found with horn switch
depressed or, if continuity is found with horn switch
released, repair horn switch or wiring as required.
See Horn Switch Remove/Install in this group for ser-
vice procedures.
If all relay connections check OK, proceed to next
step.
(3) With the horn relay still removed, check the
horn relay by performing the following tests.
²A relay in the de-energized position should have
continuity between terminal 87A and terminal 30,
and no continuity between terminal 87 and terminal
30.
²Resistance value between terminals 85 and 86
(electromagnet) is 7565 ohms.²Connect a battery to terminals 85 and 86. There
should now be continuity between terminal 87 and
terminal 30.
If relay fails any of the above tests, replace faulty
relay. If relay checks OK, reinstall and proceed to
next step.
(4) Disconnect wiring at horn terminal. Depress
horn switch. There should be battery voltage at the
horn wiring connector. If not, repair wiring to relay.
If OK, proceed to next step.
(5) Measure the resistance between the horn
bracket and a good chassis ground. The meter should
read zero ohms. If not, clean and tighten ground con-
nection between horn mounting screw and bracket. If
OK, replace faulty horn(s).
Fig. 1 Horn Relay Connections-XJ
Fig. 2 Horn Relay Connections-YJ
8G - 2 HORNSJ
VEHICLE SPEED CONTROL SYSTEM
CONTENTS
page page
DIAGNOSIS............................. 2
GENERAL INFORMATION.................. 1SERVICE PROCEDURES................... 9
GENERAL INFORMATION
The vehicle speed control system (Fig. 1) is an
available option on all XJ (Cherokee) models. The
system is electronically controlled and vacuum oper-
ated. Following are general descriptions of the major
components in the vehicle speed control system. Re-
fer to Group 8W - Wiring Diagrams for complete cir-
cuit descriptions and diagrams.
SPEED CONTROL SERVO
The speed control servo is mounted to a bracket on
the right side inner fender shield in the engine com-
partment. The servo unit consists of a solenoid valve
body, a vacuum servo and the mounting bracket. The
PCM controls the solenoid valve body. The solenoid
valve body controls the application and release of
vacuum to the diaphragm of the vacuum servo. The
servo unit cannot be repaired and is serviced only as
a complete assembly.
SPEED CONTROL SWITCH
The speed control switch module is mounted to the
center of the steering wheel below the driver's airbag
module. The PCM monitors the state of the speed
control switches. The individual switches are labeled:
OFF/ON, RESUME/ACCEL, SET/COAST. Refer to
the owner's manual for more information on speed
control switch functions and setting procedures. The
individual switches cannot be repaired. If one switch
fails, the entire switch module must be replaced.
STOP LAMP SWITCH
Vehicles with the speed control option use a dual
function stop lamp switch. The switch is mounted in
the same location as the conventional stop lamp
switch, on the brake pedal mounting bracket under
the instrument panel. The PCM monitors the state of
the dual function stop lamp switch. Refer to Group 5
- Brakes for more information on stop lamp switch
service and adjustment procedures.
SERVO CABLE
The speed control servo cable is connected betweenthe speed control vacuum servo diaphragm and the
throttle control linkage. This cable causes the throt-
tle control linkage to open or close the throttle valve
in response to movement of the vacuum servo dia-
phragm.
POWERTRAIN CONTROL MODULE
The speed control electronic control circuitry is in-
tegrated into the Powertrain Control Module (PCM).
The PCM is located in the engine compartment on
the left side inner fender shield. The PCM speed con-
trol functions are monitored by the On-Board Diag-
nostics (OBD). All OBD-sensed systems are
monitored by the PCM. Each monitored circuit is as-
signed a Diagnostic Trouble Code (DTC). The PCM
will store a DTC in electronic memory for any failure
it detects. See Using On-Board Diagnostic System in
this group for more information. The PCM cannot be
repaired and must be replaced if faulty.
VACUUM RESERVOIR
The vacuum reservoir is mounted behind the left
end of the front bumper bar. The reservoir contains a
one-way check valve to trap engine vacuum in the
reservoir. When engine vacuum drops, as in climbing
a grade while driving, the reservoir supplies the vac-
uum needed to maintain proper speed control opera-
tion. The vacuum reservoir cannot be repaired and
must be replaced if faulty.
VEHICLE SPEED SENSOR
The Vehicle Speed Sensor (VSS) is a pulse genera-
tor mounted to an adapter near the transmission
(two-wheel drive) or transfer case (four-wheel drive)
output shaft. The sensor is driven through the
adapter by a speedometer pinion gear. The VSS pulse
signal to the speedometer/odometer is monitored by
the PCM speed control circuitry to determine vehicle
speed and to maintain speed control set speed. Refer
to the appropriate Powertrain Diagnostic Procedures
manual for testing of this component. Refer to Group
14 - Fuel System for service of this component.
JVEHICLE SPEED CONTROL SYSTEM 8H - 1
TURN SIGNAL AND HAZARD WARNING SYSTEMS
CONTENTS
page page
DIAGNOSIS............................. 3
GENERAL INFORMATION.................. 1SERVICE PROCEDURES................... 5
GENERAL INFORMATION
Following are general descriptions of the major
components in the XJ (Cherokee)/YJ (Wrangler)
model turn signal and hazard warning systems. Refer
to Group 8W - Wiring Diagrams for complete circuit
descriptions and diagrams.
TURN SIGNAL SYSTEM
With the ignition switch in the ON or ACCESSORY
position and the turn signal switch lever (YJ) or
multi-function switch control lever (XJ) moved up
(right turn) or down (left turn), the turn signal sys-
tem is activated.
When the turn signal system is activated, the se-
lected (right or left) turn signal indicator lamp, front
park/turn signal lamp and rear tail/stop/turn signal
lamp bulb filaments will flash. With the headlamp
switch in the OFF position, the turn and front side
marker lamps flash in unison. With the headlamp
switch in the ON position, the turn and front side
marker lamps flash alternately.
HAZARD WARNING SYSTEM
The hazard warning is activated by a switch button
located below the ignition lock cylinder (YJ) or on the
top of the steering column (XJ) between the steering
wheel and the instrument panel. The hazard warning
flasher (YJ) or combination flasher (XJ) receives bat-
tery feed at all times, and the system is functional
regardless of ignition switch position. The hazard
warning switch button is identified with a double
triangle. On YJ models, push the switch button in to
activate the hazard warning system and pull the
button out to turn system off. On XJ models, push in
on the switch button to latch the switch and activate
the hazard warning system, and push in on the
switch button again to unlatch the switch and turn
the system off.
When the hazard warning system is activated, all
(right and left) turn signal indicator, front park/turn
signal lamp and rear tail/stop/turn signal lamp bulb
filaments will flash.
TURN SIGNAL FLASHER (YJ ONLY)
The turn signal flasher is located in the fuseblock
module. It contains one fixed contact point and one
contact point attached to a flexible bimetal arm. The
contact points are normally closed. When a turn sig-
nal is activated, current flows through the flasher. As
current flows through the bimetal arm it heats and
flexes to pull the contact points open, stopping cur-
rent flow. As the bimetal arm cools it straightens,
until the contact points close and the cycle repeats.
The standard flasher is designed to handle the cur-
rent flow requirements of the factory installed light-
ing. If supplemental lighting is added to the turn
signal circuits such as when towing a trailer with
lights, the current flow through the flasher increases.
This causes the flash rate to increase. It is recom-
mended that the standard flasher be replaced with a
heavy-duty (hazard warning) flasher when supple-
mental lighting is added.
However, when a turn signal bulb fails with a stan-
dard flasher, the remaining bulbs in that circuit will
light, but not flash. This will give the driver an indi-
cation to check the turn signal bulbs. Because a
heavy-duty flasher has different internal circuitry, a
failed bulb will not prevent the remaining bulbs in
the circuit from flashing. Therefore, it is recom-
mended that an occasional visual inspection of exte-
rior turn signal lamp operation be performed when a
heavy-duty flasher is installed.
HAZARD WARNING FLASHER (YJ ONLY)
The hazard warning flasher is located in the fuse-
block module. The hazard warning flasher contains
two normally open contact points mounted to two
flexible arms. A bimetal strip is attached between the
two arms. When the hazard warning is activated,
current flows through the flasher. As the current
flows through the bimetal strip it heats and pulls the
flexible arms together until the contact points close,
JTURN SIGNAL AND HAZARD WARNING SYSTEMS 8J - 1
SERVICE PROCEDURES
WARNING: ON VEHICLES EQUIPPED WITH AN AIRBAG,
REFER TO GROUP 8M - RESTRAINT SYSTEMS BEFORE
ATTEMPTING STEERING WHEEL COMPONENT DIAGNO-
SIS OR SERVICE. FAILURE TO TAKE PROPER PRECAU-
TIONS COULD RESULT IN ACCIDENTAL AIRBAG DE-
PLOYMENT AND POSSIBLE PERSONAL INJURY.
MULTI-FUNCTION SWITCH REMOVE/INSTALL - XJ
(1) Disconnect battery negative cable.
(2) Remove tilt lever (if equipped).
(3) Remove lower instrument panel/knee blocker
(Fig. 4).(4) Remove both upper and lower shrouds from col-
umn (Fig. 5).
(5) Remove lower fixed column shroud.
(6) Loosen steering column upper bracket nuts. Do
not remove nuts.
(7) Move upper fixed column shroud to gain access
to rear of multi-function switch (Fig. 6).
(8) Remove multi-function switch tamper proof
mounting screws (tamper proof torx bit Snap On
TTXR20B2 or equivalent required).
(9) Gently pull switch away from column. Loosen
connector screw. The screw will remain in the connec-
tor.
(10) Remove wiring connector from multi-function
switch.
(11) Reverse removal procedures to install. Tighten
fasteners as follows:
²multi-function switch connector screw - 1.9 Nzm (17
in. lbs.)
²multi-function switch retaining screws - 1.9 Nzm
(17 in. lbs.)
²steering column upper bracket nuts - 12 Nzm(110
in. lbs.).
TURN SIGNAL/HAZARD WARNING SWITCH
REMOVE/INSTALL - YJ
(1) Disconnect battery negative cable.
(2) Remove the horn button with a push and turn
motion.
(3) Remove the horn button components (Fig. 7).
(4) Turn ignition switch to LOCK position and re-
move steering wheel nut and washer.
(5) Scribe an alignment mark on the steering in
line with the mark already existing on the end of the
steering column.
Fig. 5 Steering Column Shrouds Remove/Install
Fig. 4 Lower Instrument Panel/Knee Blocker Remove/
Install
Fig. 6 Multi-Function Switch Connector
JTURN SIGNAL AND HAZARD WARNING SYSTEMS 8J - 5
WIPER AND WASHER SYSTEMS
CONTENTS
page page
DIAGNOSIS - XJ......................... 3
DIAGNOSIS - YJ........................ 12
GENERAL INFORMATION - XJ.............. 1GENERAL INFORMATION - YJ............. 10
SERVICE PROCEDURES - XJ............... 6
SERVICE PROCEDURES - YJ.............. 17
GENERAL INFORMATION - XJ
Following are general descriptions of the major
components in the XJ (Cherokee) wiper and washer
systems. Refer to Group 8W - Wiring Diagrams for
complete circuit descriptions and diagrams.
WINDSHIELD WIPER SYSTEM
A two-speed wiper system is standard equipment
on all left-hand drive XJ models. An optional inter-
mittent wipe system is available. The intermittent
wipe system is standard equipment on all right-hand
drive XJ models. The two-speed wiper system allows
the driver to select from two wiper speeds. The inter-
mittent wipe system allows the driver to select from
two wiper speeds or an intermittent wipe feature
that allows a delay between wipes of 2 to 15 seconds.
Refer to the owner's manual for more information on
wiper system controls and operation.
The wipers will operate only when the ignition
switch is in the ACCESSORY or ON position. A cir-
cuit breaker near the fuseblock module protects the
circuitry of the wiper system on left-hand drive mod-
els. The circuit breaker is in the fuseblock module on
right-hand drive models.
WINDSHIELD WASHER SYSTEM
A electrically-operated windshield washer system is
standard equipment on all XJ models. The washers will
operate only when the ignition switch is in the ACCES-
SORY or ON position. A circuit breaker near the fuse-
block module protects the circuitry of the washer
system. Refer to the owner's manual for more informa-
tion on washer system controls and operation.
LIFTGATE WIPER/WASHER SYSTEM
A liftgate wiper/washer system is an available op-
tion on XJ models. The liftgate wiper is a fixed cycle
intermittent wipe system. A single switch on the in-
strument panel controls both the liftgate wiper and
washer functions. These systems will operate only
when the ignition switch is in the ON position. Fuse
1 in the fuseblock module protects the circuitry ofboth the liftgate wiper and washer. Refer to the own-
er's manual for more information on liftgate wiper/
washer system controls and operation.
WIPER ARMS, BLADES, AND ELEMENTS
All XJ models have two 18-inch windshield wiper
blades with replaceable rubber elements (squeegees).
Models with the liftgate wiper option use a single 12-
inch wiper blade with a replaceable rubber element
(squeegee).
Caution should be exercised to protect the rubber
squeegees from any petroleum-based cleaners or con-
taminants, which will rapidly deteriorate the squee-
gee rubber. If squeegees are damaged, worn or
contaminated they must be replaced.
Wiper squeegees exposed to the weather for a long
time tend to lose their wiping effectiveness. Periodic
cleaning of the squeegees is suggested to remove de-
posits of salt and road film. The wiper blades, arms
and windshield or liftgate glass should be cleaned
with a sponge or cloth and a mild detergent or non-
abrasive cleaner. If the squeegees continue to streak
or smear, they should be replaced.
The blades are mounted to spring-loaded wiper
arms. Spring tension of the wiper arms controls the
pressure applied to the blades on the glass. The
windshield wiper arms are attached by an integral
latch to the two wiper pivots on the cowl grille panel
at the base of the windshield. The liftgate wiper arm
is attached by an integral latch directly to the lift-
gate wiper motor output shaft on the liftgate panel.
The wiper arms and blades can not be adjusted or re-
paired. If faulty, they must be replaced.
WIPER LINKAGE AND PIVOTS
The wiper pivots are fastened to the cowl top panel
with screws beneath the cowl cover/grille panel. Each
pivot assembly can be replaced by removing the cowl
grille panel, unsnapping the linkage bushing(s) from
the pivot crank arm pins, and removing the mount-
ing screws.
JWIPER AND WASHER SYSTEMS 8K - 1