1994 JEEP CHEROKEE wheel alignment

ABS BRAKE DIAGNOSIS
INDEX
page page
ABS Fault Diagnosis....................... 4
ABS System Wiring and Electrical Circuits...... 4
ABS Warning Light Display.................. 3
Brake Warning Light Display................. 4
Diagnosis Procedures...................... 3
ECU Diagnosis........................... 4
HCU Diagnosis........................... 4Loss of Sensor Input....................... 3
Operating Sound Levels.................... 3
Rear Speed Sensor Air Gap................. 3
Steering Response........................ 3
Vehicle Response in Antilock Mode............ 3
Wheel/Tire Size and Input Signals............. 3
DIAGNOSIS PROCEDURES
ABS diagnosis involves three basic steps. First is
observation of the warning light display. Second is a
visual examination for low fluid level, leaks, parking
brakes applied, or obvious damage to system compo-
nents or wires. The third step involves using the
DRB II scan tool to identify a faulty component.
The visual examination requires a check of reser-
voir fluid level and all system components. Things to
look for are leaks, loose connections, or obvious com-
ponent damage.
The final diagnosis step involves using the DRB II
scan tool to determine the specific circuit or compo-
nent at fault. The tester is connected to the ABS di-
agnostic connector in the passenger compartment.
The connector is at the driver side of the center con-
sole under the instrument panel. Refer to the DRB II
scan tool Manual for tester procedures. Also refer to
the ABS Fault Diagnosis charts at the end of this
section for additional diagnosis information.
Initial faults should be cleared and the vehicle road
tested to reset any faults that remain in the system.
Faults can be cleared with the DRB II scan tool.
REAR SPEED SENSOR AIR GAP
The front wheel sensors are fixed and cannot be ad-
justed. Only the rear sensor air gap is adjustable. Air
gap must be set with a brass feeler gauge.
Correct air gap is important to proper signal gen-
eration. An air gap that is too large may cause com-
plete loss of sensor input. Or, a gap that is too small
could produce a false input signal, or damaging con-
tact between the sensor and tone ring.
WHEEL/TIRE SIZE AND INPUT SIGNALS
Antilock system operation is dependant on accurate
signals from the wheel speed sensors. Ideally, the ve-
hicle wheels and tires should all be the same size
and type. However, the Jeep ABS system is designed
to function with a compact spare tire installed.
OPERATING SOUND LEVELS
The ABS pump and solenoid valves may produce
some sound as they cycle on and off. This is a normal
condition and should not be mistaken for faulty oper-
ation.
VEHICLE RESPONSE IN ANTILOCK MODE
During antilock braking, the HCU solenoid valves
cycle rapidly in response to ECU inputs.
The driver will experience a pulsing sensation
within the vehicle as the solenoids decrease, hold, or
increase pressure as needed. A pulsing brake pedal
will also be noted.
The pulsing sensation occurs as the solenoids cycle
during antilock mode braking. A slight pulse in the
brake pedal may also be noted during the dynamic
self check part of system initialization.
STEERING RESPONSE
A modest amount of steering input is required dur-
ing extremely high deceleration braking, or when
braking on differing traction surfaces. An example of
differing traction surfaces would be when the left
side wheels are on ice and the right side wheels are
on dry pavement.
LOSS OF SENSOR INPUT
Sensor malfunctions will most likely be due to
loose connections, damaged sensor wires, incorrect
rear sensor air gap, or a malfunctioning sensor. Ad-
ditional causes of sensor faults would be sensor and
tone ring misalignment or damage.
ABS WARNING LIGHT DISPLAY
ABS Light Illuminates At Startup
The amber ABS light illuminates at startup as
part of the system self check feature. The light illu-
minates for 2-3 seconds then goes off as part of the
normal self check routine.
ABS Light Remains On After Startup
An ABS system fault is indicated when the light
remains on after startup. Diagnosis with the DRB II
JBRAKES 5 - 3

(6) Lower vehicle enough for access to parking
brake lever or foot pedal.Then fully apply parking
brakes. Leave brakes applied until adjustment is
complete.
(7) Raise vehicle again.
(8) Mark tensioner rod 6.5 mm (1/4 in.) from ten-
sioner bracket (Fig. 16).
(9) Tighten adjusting nut at equalizer until mark
on tensioner rod moves into alignment with ten-
sioner bracket (Fig. 16).Do not loosen/tighten
equalizer adjusting nut for any reason after
completing adjustment.
(10) Lower vehicle until rear wheels are 15-20 cm
(6-8 in.) off shop floor.
(11) Release parking brake lever and verify that
rear wheels rotate freely without drag.
(12) Lower vehicle.
Fig. 16 Placing Adjustment Mark On Tensioner Rod
5 - 64 PARKING BRAKESJ

CLUTCH DIAGNOSIS
INDEX
page page
Clutch Problem Causes..................... 3
General Diagnosis Information................ 3Inspection and Diagnosis Charts.............. 4
GENERAL DIAGNOSIS INFORMATION
Unless the cause of a clutch problem is obvious, ac-
curate problem diagnosis will usually require a road
test to confirm a problem. Component inspection will
then be required to determine the actual problem
cause.
During a road test, drive the vehicle at normal
speeds. Shift the transmission through all gear
ranges and observe clutch action. If chatter, grab,
slip, or improper release is experienced, remove and
inspect the clutch components. However, if the prob-
lem is noise or hard shifting, further diagnosis may
be needed as the transmission or another driveline
component may be at fault. Careful observation dur-
ing the test will help narrow the problem area.
CLUTCH PROBLEM CAUSES
CONTAMINATION
Fluid contamination is a frequent cause of clutch
malfunctions. Oil, water, or clutch fluid on the clutch
contact surfaces will cause faulty operation. The
usual result is chatter, slip and grab.
During inspection, note if any components are con-
taminated with oil, hydraulic fluid, or water/road
splash.
Oil contamination indicates a leak at either the
rear main seal or transmission input shaft. Oil leak-
age produces a residue of oil on the housing interior
and on the clutch cover and flywheel. Heat buildup
caused by slippage between the cover, disc and fly-
wheel, can sometimes bake the oil residue onto the
components. The glaze-like residue ranges in color
from amber to black.
Road splash contamination means dirt/water is en-
tering the clutch housing due to loose bolts, housing
cracks, or through hydraulic line openings. Driving
through deep water puddles can force water/road
splash into the housing through such openings.
Clutch fluid leaks are from loose or damaged slave
cylinder fluid lines and connecting fittings. However,
clutch fluid leaks will usually be noted and corrected
before severe contamination occurs.
CLUTCH MISALIGNMENT
Clutch components must be in proper alignment
with the crankshaft and transmission input shaft.Misalignment caused by excessive runout or warpage
of any clutch component will cause grab, chatter and
improper clutch release.
Flywheel Runout
Check flywheel runout whenever misalignment is
suspected. Flywheel runout should not exceed 0.08
mm (0.003 in.). Measure runout at the outer edge of
the flywheel face with a dial indicator. Mount the in-
dicator on a stud installed in place of one of the fly-
wheel bolts.
Common causes of runout are:
²heat warpage
²improper machining
²incorrect bolt tightening
²improper seating on crankshaft flange shoulder
²foreign material on crankshaft flange
Flywheel machining is not recommended. The fly-
wheel clutch surface is machined to a unique contour
and machining will negate this feature. However,
minor flywheel scoring can be cleaned up by hand
with 180 grit emery, or with surface grinding equip-
ment. Remove only enough material to reduce scor-
ing (approximately 0.001 - 0.003 in.). Heavy stock
removal isnot recommended.Replace the flywheel
if scoring is severe and deeper than 0.076 mm (0.003
in.). Excessive stock removal can result in flywheel
cracking or warpage after installation; it can also
weaken the flywheel and interfere with proper clutch
release.
Clean the crankshaft flange before mounting the
flywheel. Dirt and grease on the flange surface may
cock the flywheel causing excessive runout. Use new
bolts when remounting a flywheel and secure the
bolts with Mopar Lock And Seal. Tighten flywheel
bolts to specified torque only. Overtightening can dis-
tort the flywheel hub causing runout.
Clutch Cover And Disc Runout
Check the clutch disc before installation. Axial
(face) runout of anewdisc should not exceed 0.50
mm (0.020 in.). Measure runout about 6 mm (1/4 in.)
from the outer edge of the disc facing. Obtain an-
other disc if runout is excessive.
Check condition of the clutch before installation. A
warped cover or diaphragm spring will cause grab
and incomplete release or engagement. Be careful
JCLUTCH DIAGNOSIS 6 - 3

when handling the cover and disc. Impact can distort
the cover, diaphragm spring, release fingers and the
hub of the clutch disc.
Use an alignment tool when positioning the disc on
the flywheel. The tool prevents accidental misalign-
ment which could result in cover distortion and disc
damage.
A frequent cause of clutch cover distortion (and
consequent misalignment) is improper bolt tighten-
ing. To avoid warping the cover, the bolts must tight-
ened alternately (diagonal pattern) and evenly (2-3
threads at a time) to specified torque.
Clutch Housing Misalignment
Clutch housing alignment is important to proper
clutch operation. The housing maintains alignment
between the crankshaft and transmission input shaft.
Misalignment can cause clutch noise, hard shifting,
incomplete release and chatter. It can also result in
premature wear of the pilot bearing, cover release
fingers and clutch disc. In severe cases, misalign-
ment can also cause premature wear of the transmis-
sion input shaft and shaft bearing.
Housing misalignment is generally caused by in-
correct seating on the engine or transmission, loose
housing bolts, missing alignment dowels or housing
damage. Infrequently, misalignment may also be
caused by housing mounting surfaces that are not
completely parallel. Misalignment can be corrected
with shims.INSTALLATION METHODS AND PARTS
USAGE
Distortion of clutch components during installation
and the use of non-standard components are addi-
tional causes of clutch malfunction.
Improper clutch cover bolt tightening can distort
the cover. The usual result is clutch grab, chatter
and rapid wear. Tighten the cover bolts as described
in Clutch Service section.
An improperly seated flywheel and/or clutch hous-
ing are additional causes of clutch failure. Improper
seating will produce misalignment and additional
clutch problems.
The use of non-standard or low quality parts will
also lead to problems and wear. Use recommended
factory quality parts to avoid comebacks.
INSPECTION AND DIAGNOSIS CHARTS
The clutch inspection chart (Fig. 1) outlines items
to be checked before and during clutch installation.
Use the chart as a check list to help avoid overlook-
ing potential problem sources during service opera-
tions.
The diagnosis charts describe common clutch prob-
lems, causes and correction. Fault conditions are
listed at the top of each chart. Conditions, causes and
corrective action are outlined in the indicated col-
umns.
The charts are provided as a convenient reference
when diagnosing faulty clutch operation.
6 - 4 CLUTCH DIAGNOSISJ

CLUTCH SERVICE
INDEX
page page
Clutch Cover and Disc Installation............ 10
Clutch Cover and Disc Removal............. 10
Clutch Fluid Level........................ 14
Clutch Housing Replacement................ 11
Clutch Hydraulic Linkage Installation.......... 12
Clutch Hydraulic Linkage Removal........... 11Clutch Pedal Installation................... 15
Clutch Pedal Removal..................... 15
Clutch Safety Precautions.................. 10
Flywheel Service......................... 15
Pilot Bearing Replacement................. 11
Release Bearing Replacement............... 11
CLUTCH SAFETY PRECAUTIONS
WARNING: EXERCISE CARE WHEN SERVICING
CLUTCH COMPONENTS. DUST AND DIRT ON
CLUTCH PARTS USE MAY CONTAIN ASBESTOS FI-
BERS. BREATHING EXCESSIVE CONCENTRATIONS
OF THESE FIBERS CAN CAUSE SERIOUS BODILY
HARM. WEAR A RESPIRATOR DURING SERVICE
AND NEVER CLEAN CLUTCH COMPONENTS WITH
COMPRESSED AIR OR WITH A DRY BRUSH. EI-
THER CLEAN THE COMPONENTS WITH A WATER
DAMPENED RAGS OR USE A VACUUM CLEANER
SPECIFICALLY DESIGNED FOR REMOVING ASBES-
TOS FIBERS AND DUST. DO NOT CREATE DUST
BY SANDING A CLUTCH DISC. REPLACE THE DISC
IF THE FRICTION MATERIAL IS DAMAGED OR
CONTAMINATED. DISPOSE OF ALL DUST AND
DIRT CONTAINING ASBESTOS FIBERS IN SEALED
BAGS OR CONTAINERS. THIS WILL HELP MINIMIZE
EXPOSURE TO YOURSELF AND TO OTHERS. FOL-
LOW ALL RECOMMENDED SAFETY PRACTICES
PRESCRIBED BY THE OCCUPATIONAL SAFETY
AND HEALTH ADMINISTRATION (OSHA) AND THE
ENVIRONMENTAL SAFETY AGENCY (EPA), FOR
THE HANDLING AND DISPOSAL OF PRODUCTS
CONTAINING ASBESTOS.
CLUTCH COVER AND DISC REMOVAL
(1) Remove transmission. Refer to procedures in
Group 21.
(2) If original clutch cover will be reinstalled,
mark position of cover on flywheel for assembly ref-
erence. Use paint or a scriber for this purpose.
(3) If clutch cover is to be replaced, cover bolts can
be removed in any sequence. However, if original
cover will be reinstalled, loosen cover bolts evenly
and in rotation to relieve spring tension equally.
This is necessary avoid warping cover.
(4) Remove cover bolts and remove cover and disc
(Fig. 2).
CLUTCH COVER AND DISC INSTALLATION
(1) Lightly scuff sand flywheel face with 180 grit
emery cloth. Then clean surface with a wax and
grease remover.
(2) Lubricate pilot bearing with Mopar high tem-
perature bearing grease.
(3) Check runout and free operation of new clutch
disc as follows:
(a) Slide disc onto transmission input shaft
splines. Disc should slide freely on splines.
(b) Leave disc on shaft and check face runout
with dial indicator. Check runout at disc hub and
about 6 mm (1/4 in.) from outer edge of facing.
(c) Face runout should not exceed 0.5 mm (0.020
in.). Obtain another clutch disc if runout exceeds
this limit.
(4) Position clutch disc on flywheel. Be sure side of
disc marked flywheel side is positioned against fly-
wheel (Fig. 2). If disc is not marked, be sure flat side
of disc hub is toward flywheel.
(5) Insert clutch alignment tool in clutch disc (Fig.
3).
(6) Insert alignment tool in pilot bearing and posi-
tion disc on flywheel. Be sure disc hub is positioned
correctly. Side of hub marked Flywheel Side should
face flywheel (Fig. 2). If disc is not marked, place flat
side of disc against flywheel.
(7) Position clutch cover over disc and on flywheel
(Fig. 3).
(8) Install clutch cover bolts finger tight.
(9) Tighten cover bolts evenly and in rotation a
few threads at a time.Cover bolts must be tight-
ened evenly and to specified torque to avoid dis-
torting cover. Tightening torques are 31 Nzm (23
ft. lbs.) on 2.5L engines and 54 Nzm (40 ft. lbs.) on
4.0L engines.
(10) Apply light coat of Mopar high temperature
bearing grease to pilot bearing hub and splines of
transmission input shaft.Do not overlubricate
shaft splines. This will result in grease contami-
nation of disc.
(11) Install transmission (Fig. 4). Refer to proce-
dures in Group 21.
6 - 10 CLUTCH SERVICEJ

RELEASE BEARING REPLACEMENT
(1) Remove transmission as described in Group 21.
(2) Disconnect release bearing from release lever
and remove bearing (Fig. 5).
(3) Inspect bearing slide surface of transmission
front bearing retainer. Replace retainer if slide sur-
face is scored, worn, or cracked.
(4) Inspect release fork and fork pivot. Be sure
pivot is secure and in good condition. Be sure fork is
not distorted or worn. Replace release fork retainer
spring if bent or damaged in any way.
(5) Lubricate crankshaft pilot bearing with Mopar
high temperature bearing grease. Apply grease to
end of long shank, small diameter flat blade screw-
driver. Then insert tool through clutch disc hub to
reach bearing.
(6) Lubricate input shaft splines, bearing retainer
slide surface, fork pivot and release fork pivot sur-face with Mopar high temperature grease.
(7) Install new release bearing. Be sure bearing is
properly secured to release fork.
(8) Install transmission as described in Group 21.
PILOT BEARING REPLACEMENT
(1) Remove transmission. Refer to Group 21 for
procedure.
(2) Remove clutch cover and disc.
(3) Remove pilot bearing. Use internal (blind hole)
puller such those as supplied in Snap On Tool Set
CG40CB to remove bearing.
(4) Lubricate new bearing with Mopar high tem-
perature bearing grease.
(5) Start new bearing into crankshaft by hand.
Then seat bearing with clutch alignment tool (Fig.
6).
(6) Lightly scuff sand flywheel surface with 180
grit emery cloth. Then clean surface with wax and
grease remover.
(7) Install clutch disc and cover as described in
this section.
(8) Install transmission. Refer to Group 21 for pro-
cedure.
CLUTCH HOUSING REPLACEMENT
The AX 15 clutch housing is removable and can be
replaced when the transmission is out of the vehicle.
The bolts attaching the housing to the transmis-
sion case are located inside the housing (Fig. 7). Rec-
ommended tightening torque for the clutch housing-
to-transmission bolts is 38 Nzm (28 ft. lbs.).
Be sure the transmission and housing mating
surfaces are clean before installing an original,
or replacement clutch housing. Dirt/foreign ma-
terial trapped between the housing and trans-
mission will cause misalignment. If
misalignment is severe enough, the result will be
clutch drag, incomplete release and hard shift-
ing.
CLUTCH HYDRAULIC LINKAGE REMOVAL
The clutch master cylinder, slave cylinder and
connecting line are serviced as an assembly
only. The linkage components cannot be over-
hauled or serviced separately. The cylinders and
connecting line are sealed units. Also note that
removal/installation procedures for right and
left hand drive models are basically the same.
Only master cylinder location is different.
(1) Raise vehicle.
(2) Remove fasteners attaching slave cylinder to
clutch housing.
(3) Remove slave cylinder from clutch housing
(Fig. 8).
(4) Disengage clutch fluid line from body clips.
(5) Lower vehicle.
Fig. 2 Clutch Disc Position
Fig. 3 Typical Method Of Aligning Clutch Disc
JCLUTCH SERVICE 6 - 11

Check flywheel runout if misalignment is sus-
pected. Runout should not exceed 0.08 mm (0.003
in.). Measure runout at the outer edge of the fly-
wheel face with a dial indicator. Mount the dial indi-
cator on a stud installed in place of one of the
flywheel attaching bolts.
Clean the crankshaft flange before mounting the
flywheel. Dirt and grease on the flange surface may
cock the flywheel causing excessive runout.
Check condition of the flywheel hub and attaching
bolts. Replace the flywheel if the hub exhibits cracks
in the area of the attaching bolt holes.
Install new attaching bolts whenever the flywheel
is replaced and use Mopar Lock N' Seal, or Loctite
242 on the replacement bolt threads.
Recommended flywheel bolt torques are:
²142 Nzm (105 ft. lbs.) for 6-cylinder flywheels
²68 Nzm (50 ft. lbs.) plus an additional turn of 60É
for 4-cylinder flywheels
Inspect the teeth on the starter ring gear.If the
teeth are worn or damaged, the flywheel should
be replaced as an assembly. This is the recom-
mended and preferred method of repair.
In cases where a new flywheel is not readily avail-
able, a replacement ring gear can be installed. How-
ever, the following precautions must be observed to
avoid damaging the flywheel and replacement gear.
(a) Mark position of the old gear for alignment
reference on the flywheel. Use a scriber for this
purpose.
(b) Wear protective goggles or approved safety
glasses. Also wear heat resistent gloves when han-
dling a heated ring gear.
(c) Remove the old gear by cutting most of the
way through it (at one point) with an abrasive cut-
off wheel. Then complete removal with a cold chisel
or punch.(d) The ring gear is a shrink fit on the flywheel.
This means the gear must be expanded by heating
in order to install it.The method of heating and
expanding the gear is extremely important.
Every surface of the gear must be heated at the
same time to produce uniform expansion. An oven
or similar enclosed heating device must be used.
Temperature required for uniform expansion is ap-
proximately 375É F.
CAUTION: Do not use an oxy/acetylene torch to re-
move the old gear, or to heat and expand a new
gear. The high temperature of the torch flame can
cause localized heating that will damage the fly-
wheel. In addition, using the torch to heat a replace-
ment gear will cause uneven heating and
expansion. The torch flame can also anneal the
gear teeth resulting in rapid wear and damage after
installation.
(e) The heated gear must be installed evenly to
avoid misalignment or distortion. A shop press and
suitable press plates should be used to install the
gear if at all possible.
(f) Be sure to wear eye and hand protection.
Heat resistent gloves and safety goggles are needed
for personal safety. Also use metal tongs, vise grips,
or similar tools to position the gear as necessary
for installation.
(g) Allow the flywheel and ring gear to cool down
before installation. Set the assembly on a work-
bench and let it cool in normal shop air.
CAUTION: Do not use water, or compressed air to
cool the flywheel. The rapid cooling produced by
water or compressed air can distort, or crack the
gear and flywheel.
6 - 16 CLUTCH SERVICEJ

SERVICE PROCEDURES
INDEX
page page
Servo Cable Replacement................... 9
Speed Control Servo Replacement............ 9Speed Control Switch Replacement............ 9
SPEED CONTROL SERVO REPLACEMENT
REMOVAL
(1) Disconnect vacuum hose at servo (Figs. 1 and
2).
(2) Disconnect electrical connector at servo.
(3) Remove 2 nuts from cable sleeve.
(4) Pull speed control cable away from servo to ex-
pose cable retaining clip.
(5) Remove clip attaching cable to servo.
(6) Pull servo away from mounting bracket.
INSTALLATION
(1) Insert servo studs through holes in servo
mounting bracket.
(2) With throttle blocked to full open position,
align hole in cable sleeve with hole in servo pin and
install retaining clip.
(3)
Insert servo studs through holes in cable sleeve.
(4) Install 2 attaching nuts and tighten to 6 Nzm
(50 in. lbs.).
(5) Connect vacuum hose to servo.
(6) Connect electrical connector to servo terminals.
SERVO CABLE REPLACEMENT
CAUTION: Use finger pressure only to remove the
speed control cable connector at the bell crank. Pli-
ers or screwdriver can break connector requiring
complete cable replacement.
(1) Using finger pressure only, remove speed con-
trol cable connector at bell crank by pushing connec-
tor off the bell crank (Fig. 3). DO NOT try to pull
connector off perpendicular to the bell crank.
(2) Squeeze tabs on speed control cable and push
out of locking plate (Fig. 4).
(3) Pull cable out of cable guide.
(4) Remove 2 nuts and cable housing from servo.
(5) Release cable clip from servo cable and remove
servo cable.
(6) To install, reverse the removal procedure.
SPEED CONTROL SWITCH REPLACEMENT
(1) Disconnect negative cable from battery.
(2) Remove horn button with a push and turn mo-
tion.
(3) Remove horn button components (Fig. 5).
(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. 2 Speed Control ServoÐRight Hand Drive
Fig. 1 Speed Control ServoÐLeft Hand Drive
JVEHICLE SPEED CONTROL SYSTEM 8H - 9