
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

SPEED CONTROL SWITCH
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) Disconnect battery negative cable. Remove
speed control switch from steering wheel.
(2) Check speed control switch continuity as shown
in chart (Fig. 2). If OK, reinstall switch. If not OK,
replace switch.
STOP LAMP SWITCH
(1) Unplug the connector at the stop lamp switch.
With the brake pedal released, check switch for con-
tinuity at the switch side of connector (Fig. 3) as fol-
lows:
(a) There should be continuity between the black
and white/pink wires.
(b) There should be continuity between the yel-
low/red and dark blue/red wires.
(c) There should be no continuity between pink
and white wires.(2) With the brake pedal applied, check switch for
continuity at the switch side of connector (Fig. 3) as
follows:
(a) There should be continuity between pink and
white wires.
(b) There should be no continuity between black
and white/pink wires.
(c) There should be no continuity between the
yellow/red and dark blue/red wires.
(3) If the above results are not obtained, check the
stop lamp switch adjustment. If adjustment is OK,
replace faulty switch. Refer to Group 5 - Brakes for
adjustment and service procedures.
VACUUM SUPPLY TEST
(1) Disconnect vacuum hose at the servo and in-
stall a vacuum gauge in the hose.
(2) Start engine and observe gauge at idle. Vacuum
gauge should read at least ten inches of mercury.
(3) If vacuum does not meet this requirement,
check for vacuum leaks or poor engine performance.
SPEED CONTROL SERVO
(1) Check fuse F13 in the PDC. If OK, go to next
step. If not OK, replace fuse.
(2) Turn ignition switch to the ON position. Check
for battery voltage at fuse F13. If OK, go to next
step. If not OK, repair open circuit to ignition switch
as required.
(3) Connect the negative lead of a voltmeter to a
good chassis ground near the servo. Unplug the
4-way connector going to the servo (Fig. 4 or 5). Push
the speed control switch to the ON position. Check
for battery voltage at servo harness connector cavity
Fig. 2 Speed Control Switch Continuity
Fig. 3 Stop Lamp Switch Connector
8H - 6 VEHICLE SPEED CONTROL SYSTEMJ

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

DIAGNOSIS
When diagnosing the turn signal or hazard warning
circuits, remember that high generator output can
burn out bulbs rapidly and repeatedly. If this is a
problem on the vehicle being diagnosed, refer to
Group 8A - Battery/Starting/Charging Systems Diag-
nostics to test charging system.
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.
TURN SIGNAL/HAZARD WARNING SYSTEM - XJ
(1) Turn ignition switch to ON position. Actuate the
turn signal lever or hazard warning button. Observe
the turn indicator lamp(s) in the instrument cluster.
If the flash rate is very high, check for a turn signal
bulb that is not lit. Replace that bulb or repair cir-
cuits to that lamp, as required. Test operation. If turn
indicator does not light, continue to next step.
(2) Remove and inspect fuse 8 (turn signals) in
fuseblock module, or fuse F13 (hazard warning) in the
Power Distribution Center. Replace fuse, if required.
(3) Remove combination flasher from relay center
and replace with a known good unit. Test operation of
turn signal and hazard warning systems. If OK, re-place faulty combination flasher. If not OK, remove
test flasher and go to next step.
(4) With ignition switch in ON position, check for
battery voltage at cavity for flasher terminal J1 (Fig.
2). If OK, go to next step. If not OK, repair circuit to
ignition switch as required.
(5) With ignition switch in OFF position, check for
battery voltage at cavity for flasher terminal J2. If
OK, go to next step. If not OK, repair circuit to Power
Distribution Center as required.
(6) With ignition switch in OFF position, check for
continuity between cavity for flasher terminal J5 and
a good ground. There should be continuity. If OK, go
to next step. If not OK, repair circuit to ground as
required.
(7) Locate the multi-function switch connector. See
Multi-Function Switch, in this group. Check for conti-
nuity between cavity for flasher terminal J3 and cav-
ity 13 of the multi-function switch connector. There
should be continuity. If OK, go to next step. If not OK,
repair open circuit as required.
(8) Check for continuity between cavity for flasher
terminal J4 and cavity 17 of the multi-function switch
connector. There should be continuity. If OK, test
multi-function switch. If not OK, repair open circuit
as required.
TURN SIGNAL SYSTEM - YJ
A turn signal indicator lamp that remains lit (with-
out flashing) is an indication of a burned out exterior
turn signal bulb or faulty exterior lamp circuit. Check
Fig. 2 Combination Flasher Circuit - XJ
JTURN SIGNAL AND HAZARD WARNING SYSTEMS 8J - 3

lamps and repair circuits or replace bulbs as re-
quired. If system still does not function properly, pro-
ceed as follows.
(1) Locate fuseblock module under driver's side of
instrument panel. Remove and inspect fuse 4. If OK,
go to next step. If not OK, replace fuse as required.
(2) Replace turn signal flasher (light blue can in
fuseblock module) with a known good unit. Test op-
eration. If OK, replace faulty turn signal flasher. If
not OK, remove test flasher and go to next step.
(3) Turn ignition switch to ACCESSORY position.
Check for battery voltage at flasher cavity on left
(closest to hazard flasher). If OK, go to next step. If
not OK, repair circuit to fuse 4 as required.
(4) Turn ignition switch to OFF position. See Turn
Signal/Hazard Warning Switch Remove/Install to lo-
cate steering column connector. Unplug connector.
(5) Turn ignition switch to ACCESSORY position.
Check for battery voltage at connector terminal L. If
OK, replace turn signal/hazard warning switch. If not
OK, repair circuit between turn signal flasher and
steering column connector.
HAZARD WARNING SYSTEM - YJ
(1) Locate Power Distribution Center (PDC) near
battery tray in engine compartment. Remove and in-
spect fuse F5. If OK, go to next step. If not OK,
replace fuse as required.(2) Replace hazard warning flasher (metal can in
fuseblock module) with a known good unit. Test op-
eration. If OK, replace faulty hazard warning flasher.
If not OK, remove test flasher and go to next step.
(3) Check for battery voltage at flasher cavity on
left (closest to hazard flasher). If OK, go to next step.
If not OK, repair circuit to fuse F5 in PDC as re-
quired.
(4) See Turn Signal/Hazard Warning Switch Re-
move/Install to locate steering column connector. Un-
plug connector.
(5) Check for battery voltage at connector terminal
K. If OK, replace turn signal/hazard warning switch.
If not OK, repair circuit between hazard warning
flasher and steering column connector.
MULTI-FUNCTION SWITCH - XJ
(1) Access multi-function switch connector and re-
move. See service procedures for Multi-Function
Switch, in this group.
(2) Using an ohmmeter, perform switch continuity
checks at the switch terminals as shown in the chart
(Fig. 3).
Fig. 3 Multi-Function Switch Continuity
8J - 4 TURN SIGNAL AND HAZARD WARNING SYSTEMSJ

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

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

WINDSHIELD WASHER SYSTEM
WITH NON-INTERMITTENT WIPE
(1) Unplug washer pump connector. Measure resis-
tance between terminal B at pump and a clean chas-
sis ground. Meter should read zero ohms. If not OK,
repair open to ground.
(2) Turn ignition switch to ACCESSORY and
washer (multi-function) switch to ON.
(a) Measure voltage at washer pump connector
terminal A. Meter should read battery voltage. If
OK, replace washer pump. If not OK, go to next
step.
(b) Measure voltage at wiper/washer switch con-
nector terminal B. Meter should read battery volt-
age. If OK, repair open to washer pump. If not OK,
replace switch.
WITH INTERMITTENT WIPE
(1) Unplug washer pump connector. Measure resis-
tance between terminal B at pump and a clean chas-
sis ground. Meter should read zero ohms. If not OK,
repair open to ground.
(2) Turn ignition switch to ACCESSORY and
washer (multi-function) switch to ON.
(a) Measure voltage at intermittent wipe module
switch connector terminal B (pink wire). Meter
should read battery voltage. If not OK, replace
wiper switch.
(b) Measure voltage at wipe module motor con-
nector terminal B (brown wire). Meter should read
battery voltage. If not OK, replace module.
(c) Measure voltage at washer pump connector
terminal A at pump. Meter should read battery
voltage. If OK, replace pump. If not OK, repair
open from wipe module.
WINDSHIELD WIPER/WASHER SWITCH
Use an ohmmeter to test for continuity (no resis-
tance) between the terminals of the switch as shown
in the Multi-Function Switch Continuity chart (Fig. 2
or 3).
INTERMITTENT WIPE MODULE
The intermittent wipe module is non-serviceable.
Refer to Group 8W - Wiring Diagrams for more infor-
mation.
The intermittent wipe module is attached to the
lower instrument panel cover near the steering col-
umn with a hook and loop fastener patch.
LIFTGATE WIPER SYSTEM
(1) Remove and inspect fuse 1. Replace faulty fuse,
if required.
(2) Turn ignition switch to ACCESSORY and lift-
gate wiper switch to WASH.(a) Measure voltage at liftgate wiper switch ter-
minal B. Meter should read battery voltage. If not
OK, repair open to fuse 1.
(b) Measure voltage at liftgate wiper switch ter-
minals A, C and D. Meter should read battery volt-
age. If not OK, replace switch.
(3) Turn ignition switch to ACCESSORY, place lift-
gate wiper switch in WIPE. Measure voltage at lift-
Fig. 2 Multi-Function Switch Continuity (Two-Speed
Wipers)
Fig. 3 Multi-Function Switch Continuity (Intermittent
Wipe)
8K - 4 WIPER AND WASHER SYSTEMS - XJJ