JEEP CHEROKEE 1988 Service Repair Manual
Page 301 of 1378
LATERAL ACCELERATION SWITCHES
See ACCELEROMETERS .
LEDS
See BULBS AND LEDS .
LENSES
LENSE INSPECTION \
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Condition Code Procedure
Application incorrect ... A ............ Require replacement.
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Broken, affecting
performance ............ A ............ Require replacement.
Broken, not affecting
performance ............ .. ........ No service suggested or
required.
Cracked ................. A ............ Require replacement.
Discolored .............. A ............ Require replacement.
Leaking ................. A .. Require repair or replacement.
Melted, affecting
performance ............ A ............ Require replacement.
Melted, not affecting
performance ............ 2 ............ Suggest replacement.
Missing ................. C ............ Require replacement.
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MASTER CYLINDERS
MASTER CYLINDER INSPECTION \
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Condition Code Procedure
Brake fluid leaking from
rear of master cylinder
bore ................... B .. Require repair or replacement.
Brake pedal drops
intermittently ......... A ........... ( 1) Require repair or
replacement.
Fluid level low ......... .. ......... ( 2) Further inspection
required.
Internal valve failure .. A .. Require repair or replacement.
Master cylinder leaking
brake fluid internally . A .. Require repair or replacement.
Piston does not return .. A .. Require repair or replacement.
Ports plugged ........... A .. Require repair or replacement.
Rubber master cylinder
cover gasket distorted
and gummy .............. A .. ( 3) Require replacement of the
gasket.
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(1) - This condition may be normal on some vehicles equipped with
anti-lock brakes.
( 2) - Refer to OEM procedures for adjusting low fluid level.
Inspect for brake hydraulic system leaks and friction
material wear.
( 3) - This condition may indicate contaminated brake fluid.
See BRAKE FLUID .
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MODULATORS
See HYDRAULIC MODULATORS .
MOTORS
See ELECTRICAL PUMPS AND MOTORS .
PARKING BRAKE SWITCHES
See SWITCHES.
PARKING BRAKE SYSTEMS
NOTE: The parking brake is an integral part of the brake
system. It is important that the parking brake function
properly when brake service is performed.
PARKING BRAKE SYSTEM INSPECTION
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Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Cable improperly
adjusted ............... B ....... Require cable adjustment.
Cable or individual
wires in the cable
are broken ............. A .... Require replacement of cable
assembly.
Cable sticking .......... A ...... Require cable lubrication.
Cable stuck inside conduit
and cannot be lubricated
so that parking brake
functions properly ..... A .... Require replacement of cable
assembly.
Inoperative ( 1) ......... A .......... Require replacement of
inoperative parts.
Parking brake
parts bent ............. B ... Require repair or replacement
of bent parts.
Parking brake
parts broken ........... A ... Require replacement of broken
parts.
Parking brake parts
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missing ................ C .. Require replacement of missing
parts.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
(1) - Inoperative includes intermittent operation.
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PADS
See FRICTION MATERIAL .
PEDAL TRAVEL SWITCHES
See SWITCHES.
PEDALS
See BRAKE PEDALS.
POWERMASTER
See HYDRO-BOOSTERS .
PUMPS
See ELECTRICAL PUMPS AND MOTORS .
PRESSURE DIFFERENTIAL SWITCHES
See SWITCHES.
PRESSURE SWITCHES
See SWITCHES.
RELAYS
NOTE: Copied from Electrical UIGs
RELAY INSPECTION
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Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Housing broken .......... A ............ Require replacement.
Housing cracked ......... 2 ............ Suggest replacement.
Inoperative ( 1) ......... A ............ Require replacement.
Missing ................. C ............ Require replacement.
Terminal broken ......... A .. Require repair or replacement.
Terminal burned,
affecting performance .. A ........... ( 2) Require repair or
replacement.
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Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose, affecting
performance ............ B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
(1) - Inoperative includes intermittent operation or out of OEM
specification.
( 2) - Determine cause and correct prior to repair or
replacement of part.
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ROTORS
Determine the need to recondition based upon individual rotor
conditions that follow. Friction material replacement does not require
rotor reconditioning unless other justifications exist. DO NOT
recondition new rotors unless they are being pressed or bolted onto an
existing hub. It is not necessary to replace rotors in axle sets.
However, when replacing or reconditioning a rotor due to the
conditions that follow, you may suggest reconditioning of the other
rotor on the same axle to eliminate uneven braking behavior.
Determine the need to replace based upon the individual rotor
conditions that follow. Reconditioning is defined as machining and
block sanding, or block sanding only. Block sanding is defined as
using 120-150 grit sandpaper with moderate to heavy force for 60
seconds per side. Always wash rotors after servicing or before
installing.
ROTOR INSPECTION
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Condition Code Procedure
Corrosion affecting
structural integrity ... A ........ ( 1) Require replacement.
Cracked ................. B ............ Require replacement.
Hard spots .............. 2 ....... Suggest reconditioning or
replacement of rotor according
to OEM specifications.
Lateral runout (wobble)
exceeds OEM
specifications ......... B ............ Require re-indexing,
reconditioning, or replacement
according to specifications.
Measured thickness is less
than OEM discard
specifications ......... B ............ Require replacement.
Rotor thickness is less
than OEM "machine to"
specifications but thicker
than "discard at"
specifications, and the
rotor does not require
reconditioning ......... 1 ........ ( 2) Suggest replacement.
Rotor thickness will be
less than OEM "machine to"
specifications after
required
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reconditioning ......... B ........ (3) Require replacement.
Surface is rust-pitted .. B ....... Require reconditioning or
replacement of rotor according
to OEM specifications.
Surface is scored ....... B ... ( 4) Require reconditioning or
replacement of rotor according
to OEM specifications.
Thickness variation
(parallelism) exceeds OEM
specifications .......... B ....... Require reconditioning or
replacement of rotor according
to OEM specifications.
( 1) - Examples of severe corrosion are: composite plate
separated from friction surfaces and cooling fins
cracked or missing.
( 2) - Only applies to vehicles for which OEM "machine to"
specifications exist. If OEM does not supply "machine
to" specifications, the rotor may be worn to discard
specifications.
( 3) - If OEM does not supply "machine to" specifications,
you may machine to discard specifications.
( 4) - Scoring is defined as grooves or ridges in the friction
contact surface. Some vehicle manufacturers require
machining when scoring exceeds their allowable
specifications.
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SELF-ADJUSTING SYSTEMS
SELF-ADJUSTING SYSTEM INSPECTION \
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Condition Code Procedure
Bent .................... A ... Require repair or replacement
of bent part.
Broken .................. A ... Require repair or replacement
of broken part.
Inoperative ............. A ........... ( 1) Require repair or
replacement of inoperative
parts.
Missing ................. C .......... Require replacement of
missing part.
Star wheel does not turn
freely ................. A .. Require repair or replacement.
( 1) - Inoperative includes intermittent operation.
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SHOE HARDWARE
See BRAKE SHOE HARDWARE .
SHOES
See FRICTION MATERIAL .
SOCKETS
See BULB SOCKETS.
SPEED SENSORS (ELECTRONIC WHEEL AND VEHICLE)
Page 306 of 1378
NOTE: Copied Vehicle Speed Sensors from Engine UIGs & added
Air Gap incorrect, loose, and wire lead misrouted. For
"contaminated" removed coolant & fuel examples from note.
SPEED SENSOR INSPECTION
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Condition Code Procedure
Air gap incorrect ....... B ....... (1) Require adjustment or
replacement.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware
threads damaged ........ A ... Require repair or replacement
of hardware.
Attaching hardware
threads stripped
(threads missing) ...... A .. Require repair or replacement
of hardware.
Connector broken ........ A .. Require repair or replacement.
Connector (Weatherpack
type) leaking ........... A .. Require repair or replacement.
Connector melted ........ A ........... ( 2) Require repair or
replacement.
Connector missing ....... C ............ Require replacement.
Contaminated ............ A ........... ( 3) Require repair or
replacement.
Inoperative ............. B ........... ( 4) Require repair or
replacement. Further
inspection required.
Lead routing incorrect .. B ..... Require rerouting according
to vehicle manufacturer's
specifications.
Leaking ................. A .. Require repair or replacement.
Loose ................... A .. Require repair or replacement.
Missing ................. C ............ Require replacement.
Resistance out of
specification .......... B .. Require repair or replacement.
Sensor housing cracked .. 2 ............ Suggest replacement.
Terminal broken ......... A .. Require repair or replacement.
Terminal burned,
affecting performance .. A ........... ( 2) Require repair or
replacement.
Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose,
affecting performance .. B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped
(threads missing) ...... A ............ Require replacement.
Wire lead conductors
exposed ................ B .. Require repair or replacement.
Wire lead corroded ...... A .. Require repair or replacement.
Wire lead misrouted ..... B . Require re-routing according to
vehicle manufacturer's
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specifications.
Wire lead open .......... A .. Require repair or replacement.
Wire lead shorted ....... A .. Require repair or replacement.
(1) - If a sensor is not adjustable, further inspection is
required to identify and correct cause.
( 2) - Determine cause and correct prior to repair or
replacement of part.
( 3) - Determine source of contamination, such as metal
particles or water. Require repair or replacement.
( 4) - Inoperative includes intermittent operation or out of OEM
specification. Some components may be serviceable; check
for accepted cleaning procedure.
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STEEL BRAKE LINES
STEEL BRAKE LINE INSPECTION \
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Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Corroded, affecting
structural integrity ... A ............ Require replacement.
Fitting incorrect (for
example, compression
fitting) ............... B ............ Require replacement.
Flare type incorrect .... B .. Require repair or replacement.
Leaking ................. A .. Require repair or replacement.
Line material incorrect
(copper, etc.) ......... B ............ Require replacement.
Restricted .............. A ............ Require replacement.
Routed incorrectly ...... B ..... Require routing correction.
Rust-pitted ............. 1 ............ Suggest replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped
(threads missing) ...... A ............ Require replacement.
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STOPLIGHT SWITCHES
See BRAKE STOPLIGHT SWITCHES .
SWITCHES
NOTE: Copied from Electrical UIGs & added "float saturated" from
old fluid level sensor switches.
STEEL BRAKE LINE INSPECTION
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Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Page 308 of 1378
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Binding, affecting
performance ............ A .. Require repair or replacement.
Binding, not affecting
performance ............ 2 .. Suggest repair or replacement.
Broken .................. A .. Require repair or replacement.
Burned, affecting
performance ............ A ........... (1) Require repair or
replacement.
Burned, not affecting
performance ............ 2 ........... ( 1) Suggest repair or
replacement.
Cracked, affecting
performance ............ A .. Require repair or replacement.
Cracked, not affecting
performance ............ 1 .. Suggest repair or replacement.
Float saturated ......... A ............ Require replacement.
Leaking ................. A .. Require repair or replacement.
Malfunctioning .......... A ........... ( 2) Require repair or
replacement.
Melted, affecting
performance ............ A ........... ( 1) Require repair or
replacement.
Melted, not affecting
performance ............ 2 ........... ( 1) Suggest repair or
replacement.
Missing ................. C ............ Require replacement.
Out of adjustment ....... B .. Require repair or replacement.
Terminal broken ......... A .. Require repair or replacement.
Terminal burned, affecting
performance ............ A ........... ( 1) Require repair or
replacement.
Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose, affecting
performance ............ B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
Won't return ............ A .. Require repair or replacement.
Worn .................... 1 ............ Suggest replacement.
( 1) - Determine cause and correct prior to repair or
replacement of part.
( 2) - Includes inoperative, intermittent operation, or failure to
perform all functions.
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TIRES
Consult the vehicle owner's manual or vehicle placard for
correct size, speed ratings, and inflation pressure of the original
tires.
TIRE INSPECTION
Page 309 of 1378
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Condition Code Procedure
Tire diameter incorrect,
affecting ABS or TCS ... A ............ Require replacement.
Tire pressure incorrect,
affecting ABS or TCS ... A .. Require repair or replacement.
Tire size incorrect,
affecting ABS or TCS ... A ............ Require replacement.
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TOOTHED RINGS (TONE WHEEL)
NOTE: Copied from Drivetrain UIGs.
If the toothed ring requires replacement and cannot be
replaced as a separate component, replace the assembly of which the
ring is a part.
TOOTHED RING INSPECTION
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Condition Code Procedure
Alignment incorrect ..... B ............... Require repair or
replacement.
Bent .................... B ............ Require replacement.
Contaminated, affecting
performance ............. A ........ Require repair. Identify
and correct cause.
Cracked ................. B ............ Require replacement.
Loose ................... A ............. Require replacement
of worn parts.
Missing ................. C ............ Require replacement.
Number of teeth
incorrect .............. B ............ Require replacement.
Teeth broken ............ A ............ Require replacement.
Teeth damaged, affecting
performance ............ A ............ Require replacement.
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VACUUM BOOSTERS
VACUUM BOOSTER INSPECTION \
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Condition Code Procedure
Applies too much assist
(oversensitive) ........ A ............ Require replacement.
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Auxiliary vacuum pump
inoperative ............ A ........... ( 1) Require repair or
replacement.
Check valve grommet
deteriorated, affecting
performance ............ A .. Require replacement of grommet.
Page 310 of 1378
Check valve grommet
deteriorated, not
affecting performance .. 1 . Suggest replacement of grommet.
Check valve inoperative . A ........... (2) Require repair or
replacement.
Check valve leaking ..... A .... Require replacement of check
valve.
Check valve missing ..... C .... Require replacement of check
valve.
Check valve noisy ....... 2 ............ Suggest replacement.
Connector broken ........ A .. Require repair or replacement.
Connector (Weatherpack
type) leaking .......... A .. Require repair or replacement.
Connector melted ........ A ........ ( 3) Require replacement.
Connector missing ....... C ............ Require replacement.
Leaking ................. A ............ Require replacement.
Terminal burned, affecting
performance ............ A ........... ( 3) Require repair or
replacement.
Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose, affecting
performance ............ B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
Vacuum hose filter
leaking ................ A .. Require replacement of filter.
Vacuum hose filter
restricted ............. A .. Require replacement of filter.
Wire lead burned ........ A .. Require repair or replacement.
Wire lead conductors
exposed ................ B .. Require repair or replacement.
Wire lead open .......... A .. Require repair or replacement.
Wire lead shorted ....... A .. Require repair or replacement.
( 1) - Inoperative includes intermittent operation or out of
OEM specification.
( 2) - Inoperative includes intermittent operation.
( 3) - Determine cause and correct prior to replacement of part.
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VACUUM HOSES
See HOSES.
VALVES
VALVE INSPECTION \
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Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of