1995 JEEP CHEROKEE steering

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

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

SERVICE PROCEDURES
SPEED CONTROL SERVO REMOVE/INSTALL
(1) Disconnect battery negative cable.
(2) Disconnect vacuum hose at servo.
(3) Remove 2 nuts on servo cable sleeve.
(4) Pull speed control cable away from servo to ex-
pose cable retaining clip (Fig. 9).
(5) Remove clip attaching cable to servo.
(6) Pull servo away from mounting bracket.
(7) To install, insert servo studs through holes in
sevo mounting bracket.
(8) Block throttle to full open position, align hole
in cable sleeve with hole in servo pin and install re-
taining clip.
(9) Reverse remaining removal procedures to in-
stall. Tighten servo mounting nuts to 6 Nzm (50 in.
lbs.).
SPEED CONTROL 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.
(1) Disconnect negative cable from battery.
(2) From underside of steering wheel, remove
speed control switch mounting screws (Fig. 10).
(3) Pull switches from wheel and unplug connector.
(4) Plug electrical connector into new switches.
(5) Install new switches with 2 screws.
Fig. 9 Servo Cable Remove/Install
Fig. 10 Speed Control Switch Remove/Install -
Typical
JVEHICLE SPEED CONTROL SYSTEM 8H - 9

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

allowing current flow to the lamps. As the bimetal
strip cools, the contact points are pushed open and
the cycle repeats.
COMBINATION FLASHER (XJ ONLY)
The combination flasher functions as both the turn
signal and hazard warning flasher on XJ models. The
combination flasher is a smart relay that is located in
the relay center under the lower instrument panel
and inboard of the steering column. The combination
flasher can not be repaired. If faulty, it must be
replaced.
The combination flasher is designed to handle the
current flow requirements of the factory installed
lighting. If supplemental lighting is added to the turn
signal circuits such as when towing a trailer with
lights, the combination flasher will automatically
compensate. This allows the flash rate to remain the
same, regardless of electrical load increases. However,
if a bulb fails in the turn signal or hazard warning
circuits, the flash rate of the remaining bulbs in that
circuit will increase to 120 flashes per minute or
higher.
TURN SIGNAL/HAZARD WARNING SWITCH
(YJ ONLY)
The turn signal and hazard warning switches are
combined into a single unit mounted within the upper
steering column bowl and beneath the steering wheel.
The turn signal lever on the left side of the steering
column is moved up or down to select the right or left
turn signal switch position. The turn signals will only
operate with the ignition switch in the ACCESSORY
or ON position.
The hazard warning button on the right side of the
steering column is pushed in to turn the hazard
warning system on, or pulled out to turn the system
off. The hazard warning system will operate regard-
less of ignition switch position. The turn signal/haz-
ard warning switch can not be repaired. If faulty, the
entire unit must be replaced.
MULTI-FUNCTION SWITCH (XJ ONLY)
The multi-function switch assembly (Fig. 1) is
mounted to the left side of the steering column. This
switch contains electrical circuitry for the following
functions:²turn signals
²hazard warning
²headlamp beam selection
²headlamp optical horn
²windshield wipers
²windshield washers.
The information contained in this group addresses
only the switch functions for the turn signal and
hazard warning circuits. For information relative to
other switch functions, refer to the appropriate group.
However, the multi-function switch can not be re-
paired. If any function of the switch is faulty, the
entire switch assembly must be replaced.
TURN SIGNAL INDICATOR LAMPS
These lamps are located in the instrument cluster.
They flash with the exterior turn signal lamps to give
the driver a visual indication that a turn signal or the
hazard warning circuit is operating. For diagnosis
and service of this component, refer to Group 8E -
Instrument Panel and Gauges.
TURN SIGNAL LAMPS
The exterior lamps included in the turn signal and
hazard warning circuits include: the front park/turn
signal, and the rear tail/stop/turn signal. For diagno-
sis and service of these lamps, refer to Group 8L -
Lamps.
Fig. 1 Multi-Function Switch
8J - 2 TURN SIGNAL AND HAZARD WARNING SYSTEMSJ

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

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