JEEP CHEROKEE 1988 Service Repair Manual
Page 281 of 1378
Before bleeding system, exhaust all vacuum from power unit by
depressing brake pedal several times. Bleed master cylinder (if
equipped) with bleeder screws. Bleed slave cylinder on vehicles
equipped with remote mount power assist units. Bleed wheel cylinders
and calipers in sequence. See BLEEDING SEQUENCE table.
BLEEDING SEQUENCE TABLE
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Application Sequence
All Models ................................ RR, LR, RF, LF
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* B RAK E S YSTE M U NIF O RM IN SPEC TIO N G UID ELIN ES *
1 988 J e ep C hero ke e
GENERAL INFORMATION
Brake Systems - Motorist Assurance Program
Standards For Automotive Repair
All Makes & Models
CONTENTS
OVERVIEW OF MOTORIST ASSURANCE PROGRAM
OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS
ACCELEROMETERS (G SENSOR OR LATERAL)
ACCUMULATORS
ANCHOR PINS
ANTI-LOCK BRAKE SYSTEMS
BACKING PLATES
BRAKE FLUID
BRAKE FRICTION MATERIAL
BRAKE PADS
BRAKE PEDALS
BRAKE SHOES
BRAKE SHOE HARDWARE
BRAKE STOPLIGHT SWITCHES
BULB SOCKETS
BULBS AND LEDS
CALIPER HARDWARE
CALIPERS
CONTROLLERS
DIGITAL RATIO AXLE CONTROLLERS AND BUFFERS (DRAC AND DRAB)
DISABLE SWITCHES
DRUMS
ELECTRICAL PUMPS AND MOTORS
ELECTRONIC CONTROLLERS
FLUID
FLUID LEVEL SENSOR SWITCHES
FOUR WHEEL DRIVE SWITCHES
FRICTION MATERIAL
G SENSORS
HOSES
HYDRAULIC MODULATORS
HYDRO-BOOSTERS
HYDRO-ELECTRIC BOOSTERS (POWERMASTER)
IGNITION DISABLE SWITCHES
LATERAL ACCELERATION SWITCHES
LEDS
LENSES
MASTER CYLINDERS
MODULATORS
MOTORS
PARKING BRAKE SWITCHES
PARKING BRAKE SYSTEMS
PADS
PEDAL TRAVEL SWITCHES
PEDALS
POWERMASTER
PUMPS
PRESSURE DIFFERENTIAL SWITCHES
PRESSURE SWITCHES
RELAYS
ROTORS
SELF-ADJUSTING SYSTEMS
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SHOE HARDWARE
SHOES
SOCKETS
SPEED SENSORS (ELECTRONIC WHEEL AND VEHICLE)
STEEL BRAKE LINES
STOPLIGHT SWITCHES
SWITCHES
TIRES
TOOTHED RINGS (TONE WHEEL)
VACUUM BOOSTERS
VACUUM HOSES
VALVES
WHEEL ATTACHING HARDWARE
WHEEL BEARINGS, RACES AND SEALS
WHEEL CYLINDERS
WIRING HARNESSES
INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP)
OVERVIEW OF MOTORIST ASSURANCE PROGRAM
The Motorist Assurance Program is the consumer outreach
effort of the Automotive Maintenance and Repair Association, Inc.
(AMRA). Participation in the Motorist Assurance Program is drawn from
retailers, suppliers, independent repair facilities, vehicle
manufacturers and industry associations.
Our organization's mission is to strengthen the relationship
between the consumer and the auto repair industry. We produce
materials that give motorists the information and encouragement to
take greater responsibility for their vehicles-through proper,
manufacturer-recommended, maintenance. We encourage participating
service and repair shops (including franchisees and dealers) to adopt:\
1) a Pledge of Assurance to their Customers and
2) the Motorist Assurance Program Standards of Service.
All participating service providers have agreed to subscribe
to this Pledge and to adhere to the promulgated Standards of Service
demonstrating to their customers that they are serious about customer
satisfaction.
These Standards of Service require that an inspection of the
vehicle's (problem) system be made and the results communicated to the\
customer according to industry standards. Given that the industry did
not have such standards, the Motorist Assurance Program successfully
promulgated industry inspection communication standards in 1994-95 for
the following systems: Exhaust, Brakes, ABS, Steering and Suspension,
Engine Maintenance and Performance, HVAC, and Electrical Systems.
Further, revisions to all of these inspection communication standards
are continually re-published. In addition to these, standards for
Drive Train and Transmissions have recently been promulgated.
Participating shops utilize these Uniform Inspection & Communication
Standards as part of the inspection process and for communicating
their findings to their customers.
The Motorist Assurance Program continues to work
cooperatively and proactively with government agencies and consumer
groups toward solutions that both benefit the customer and are
mutually acceptable to both regulators and industry. We maintain the
belief that industry must retain control over how we conduct our
business, and we must be viewed as part of the solution and not part
of the problem. Meetings with state and other government officials
(and their representatives), concerned with auto repair and/or
consumer protection, are conducted. Feedback from these sessions is
brought back to the association, and the program adjusted as needed.
To assure auto repair customers recourse if they were not
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satisfied with a repair transaction, the Motorist Assurance Program
offers mediation and arbitration through MAP/BBB-CARE and other non-
profit organizations. MAP conducted pilot programs in twelve states
before announcing the program nationally in October, 1998. During the
pilots, participating repair shops demonstrated their adherence to the
Pledge and Standards and agreed to follow the UICS in communicating
the results of their inspection to their customers. To put some
"teeth" in the program, an accreditation requirement for shops was
initiated. The requirements are stringent, and a self-policing method
has been incorporated which includes the "mystery shopping" of
outlets.
We welcome you to join us as we continue our outreach with
your support, both the automotive repair industry and your customers
will reap the benefits. Please visit MAP at our Internet site www.
motorist.org or contact us at:
1444 I Street, NW Suite 700
Washington, DC 20005
Phone (202) 712-9042 Fax (202) 216-9646
January 1999
MAP UNIFORM INSPECTION GENERAL GUIDELINES
OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS
It is MAP policy that all exhaust, brake, steering,
suspension, wheel alignment, drive-line, engine performance and
maintenance, and heating, ventilation and air conditioning, and
electrical services be offered and performed under the standards and
procedures specified in these sections.
Before any service is performed on a vehicle, an inspection
of the appropriate system must be performed. The results of this
inspection must be explained to the customer and documented on an
inspection form. The condition of the vehicle and its components will
indicate what services/part replacements may be "Required" or
"Suggested". In addition, suggestions may be made to satisfy the
requests expressed by the customer.
When a component is suggested or required to be repaired or
replaced, the decision to repair or replace must be made in the
customer's best interest, and at his or her choice given the options
available.
This section lists the various parts and conditions that
indicate a required or suggested service or part replacement.
Although this list is extensive, it is not fully inclusive. In
addition to this list, a technician may make a suggestion. However,
any suggestions must be based on substantial and informed experience,
or the vehicle manufacturer's recommended service interval and must be
documented.
Some conditions indicate that service or part replacement is
required because the part in question is no longer providing the
function for which it is intended, does not meet a vehicle
manufacturer's design specification or is missing.
Example:
An exhaust pipe has corroded severely and has a hole in it
through which exhaust gases are leaking. Replacement of the
exhaust pipe in this case is required due to functional
failure.
Example:
A brake rotor has been worn to the point where it measures
less than the vehicle manufacturer's discard specifications.
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Replacement of the rotor is required because it does not meet
design specifications.
Some conditions indicate that a service or part replacement
is suggested because the part is close to the end of its useful life
or addresses a customer's need, convenience or request. If a
customer's vehicle has one of these conditions, the procedure may be
only to suggest service.
Example:
An exhaust pipe is rusted, corroded or weak, but no leaks are
present. In this case, the exhaust pipe has not failed.
However, there is evidence that the pipe may need replacement
in the near future. Replacement of the pipe may be suggested
for the customer's convenience in avoiding a future problem.
Example:
The customer desires improved ride and/or handling, but the
vehicle's shocks or struts have not failed. In this case,
replacement may be suggested to satisfy the customer's
wishes. In this case, replacement of the shocks or struts may
not be sold as a requirement.
A customer, of course, has the choice of whether or not a
shop will service his or her vehicle. He or she may decide not to
follow some of your suggestions. When a repair is required, a MAP
shop must refuse partial service on that system if, in the judgment of
the service provider, proceeding with the work could create or
continue an unsafe condition. When a procedure states that required
or suggested repair or replacement is recommended, the customer must
be informed of the generally acceptable repair/replacement options
whether or not performed by the shop.
When presenting suggested repairs to the customer, you must
present the facts, allowing the customer to draw their own conclusions
and make an informed decision about how to proceed.
The following reasons may be used for required and suggested
services. These codes are shown in the "Code" column of the MAP
Uniform Inspection & Communications Standards that follow:
Reasons to Require Repair or Replacement
A - Part no longer performs intended purpose
B - Part does not meet a design specification (regardless of
performance)
C - Part is missing
NOTE: When a repair is required, the shop must refuse partial
service to the system in question, if the repair creates
or continues an unsafe condition.
Reasons to Suggest Repair or Replacement
1 - Part is close to the end of its useful life (just above
discard specifications, or weak; failure likely to occur
soon, etc.)
2 - To address a customer need, convenience, or request (to
stiffen ride, enhance performance, eliminate noise, etc.)
3 - To comply with maintenance recommended by the vehicle's
Original Equipment Manufacturer (OEM)
4 - Technician's recommendation based on substantial and
informed experience
NOTE: Suggested services are always optional. When presenting
suggested repairs to the customer, you must present the
facts, allowing the customer to draw their own conclusions
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and make an informed decision about how to proceed.
BRAKES
SERVICE PROCEDURES REQUIRED & SUGGESTED FOR PROPER
VEHICLE OPERATION
Some states may have specifications that differ from OEM.
Check your local/state regulations. Where state or local laws are
stricter, they take precedence over these guidelines.
ACCELEROMETERS (G SENSOR OR LATERAL)
ACCELEROMETER INSPECTION \
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Condition Code Procedure
Broken .................. A ............ Require replacement.
Connector loose ......... A .. Require repair or replacement.
Loose ................... B .. Require repair or replacement.
Missing ................. C ............ Require replacement.
Out of position ......... B ....... Require re-positioning to
vehicle manufacturer's
specifications.
Output signal incorrect . B ............ Require replacement.
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ACCUMULATORS
ACCUMULATOR INSPECTION \
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Condition Code Procedure
Leaking ................. B ............ Require replacement.
Missing ................. C ............ Require replacement.
Pre-charge incorrect .... B ............ Require replacement.
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ANCHOR PINS
See BACKING PLATES .
ANTI-LOCK BRAKE SYSTEMS
NOTE: Anti-lock brakes are an integral part of the brake system. It
is essential that the anti-lock brakes function properly when
brake service is performed.
Anti-lock brake systems are commonly referred to as "ABS" and
will be referred to as "ABS" throughout these guidelines. Some ABS
components also function as part of a traction control system (TCS).
WARNING: When diagnosing and servicing high pressure components,
observe safety procedures and equipment requirements
established by the vehicle manufacturer to reduce the
possibility of serious personal injury.
NOTE: Intermittent electrical conditions are often caused by a loss
of ground, poor connection, or water intrusion into the
wiring harness.
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NOTE: Electro-magnetic interference (EMI) may be caused by
incorrect installation of accessories or components. EMI can
result in improper system operation.
BACKING PLATES
BACKING PLATE INSPECTION \
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Condition Code Procedure
Anchor pin bent ......... B .. Require repair or replacement.
Anchor pin broken ....... A ............ Require replacement.
Anchor pin worn, affecting
structural integrity ... B ............ Require replacement.
Backing plate bent ...... B .. Require repair or replacement.
Backing plate broken .... A ............ Require replacement.
Backing plate cracked ... B .. Require repair or replacement.
Corroded, affecting
structural integrity .... A ............ Require replacement.
Loose ................... B .. Require repair or replacement.
Missing ................. C ............ Require replacement.
Shoe lands worn ......... A .. Require repair or replacement.
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BRAKE FLUID
CAUTION: Most manufacturers prohibit the use of DOT 5 brake fluid
in a system equipped with ABS.
DOT 3, DOT 4, and DOT 5.1 brake fluids are clear or light
amber in color. DOT 5 brake fluid is violet in color. Correct fluid
required for the brake system is stamped on the master cylinder cover.
BRAKE FLUID INSPECTION
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Condition Code Procedure
Beyond service interval . 3 .. Suggest flushing and refilling
with correct fluid.
Brake fluid type
incorrect .............. B .. Require flushing and refilling
with correct fluid.
Contaminated, for example,
fluid other than brake
fluid present .......... A or B ....... ( 1) Require service.
Hydraulic component ..... 3 .. Suggest flushing and refilling
overhaul or replacement with correct fluid.
Rubber master cylinder
cover gasket distorted
and gummy .............. A .......... ( 2) Require replacement
of gasket.
( 1) - If a fluid other than brake fluid is present in the brake
system which DOES affect the rubber parts, the required
service is to:
* Remove all components having rubber parts from the
system.
* Flush lines with denatured alcohol or brake cleaner
* Repair or replace all components having rubber parts
* Flush and fill with correct brake fluid. (Code A)
If a fluid other than brake fluid is present in the brake
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system which DOES NOT affect the rubber parts, the required
service is to flush and fill with the correct brake fluid.
(Code B)
( 2) - This condition may indicate contaminated brake fluid.
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BRAKE FRICTION MATERIAL
See FRICTION MATERIAL .
BRAKE PADS
See FRICTION MATERIAL .
BRAKE PEDALS
BRAKE PEDAL INSPECTION \
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Condition Code Procedure
Bent, affecting
performance ............ A .. Require repair or replacement.
Broken .................. A .. Require repair or replacement.
Pedal pad missing ....... C .... Require replacement of pedal
pad.
Pedal pad worn .......... 1 ............ Suggest replacement.
Pivot bushings worn,
affecting performance .. A .... Require replacement of pivot
bushings.
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BRAKE SHOES
See FRICTION MATERIAL .
BRAKE SHOE HARDWARE
See also SELF-ADJUSTING SYSTEMS .
BRAKE SHOE HARDWARE INSPECTION
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Condition Code Procedure
Broken .................. A ............ Require replacement.
Distorted ............... A ............ Require replacement.
Missing ................. C ............ Require replacement.
Surfaces rust-pitted .... 1 ............ Suggest replacement.
Worn, affecting
performance ............ A ............ Require replacement.
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BRAKE STOPLIGHT SWITCHES
BRAKE STOPLIGHT INSPECTION \
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Condition Code Procedure
Bent .................... B ............ Require replacement.
Broken .................. A ............ Require replacement.
Connector broken ........ A .. Require repair or replacement.
Connector (Weatherpack
type) leaking .......... A .. Require repair or replacement.
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Connector melted ........ A ........ (1) Require replacement.
Connector missing ....... C ............ Require replacement.
Missing ................. C ............ Require replacement.
Out of adjustment ....... B ........... Require adjustment or
replacement.
Output signal incorrect . B ............ Require 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.
( 1) - Determine cause and correct prior to replacement of part.
( 2) - Determine cause and correct prior to repair or replacement
of part.
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BULB SOCKETS
BULB SOCKET 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.
Broken .................. A .. Require repair or replacement.
Bulb seized in socket ... A .. Require repair or replacement.
Burned, affecting
performance ............ A .............. ( 1) Require repair
or replacement.
Burned, not affecting
performance ............ 2 .............. ( 1) Suggest repair
or replacement.
Connector broken ........ A .. Require repair or replacement.
Connector missing ....... C ............ Require replacement.
Connector (Weatherpack
type) leaking .......... A .. Require repair or replacement.
Connector melted ........ A .............. ( 2) Require repair
or replacement.
Corroded, affecting
performance ............ A .. Require repair or replacement.
Corroded, not affecting
performance ............ 2 .. Suggest repair or replacement.
Leaking ................. A .. Require repair or replacement.
Melted .................. A ........ ( 2) Require replacement.
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Shorted ................. A .. Require repair or 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.
( 1) - Determine cause and correct prior to repair or
replacement of socket.
( 2) - Determine cause and correct prior to repair or
replacement of part.
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BULBS AND LEDS
NOTE: Copied from Electrical UIGs and modified. Does not
include soldered-in components.
BULB AND LED INSPECTION
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Condition Code Procedure
Application incorrect ... B ........ ( 1) Require replacement.
Base burned, affecting
performance ............ A .............. ( 2) Require repair
or replacement.
Base burned, not affecting
performance ............ 2 .............. ( 2) Suggest repair
or replacement.
Base corroded, affecting
performance ............ A .. Require repair or replacement.
Base corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Base loose, affecting
performance ............ B .. Require repair or replacement.
Base loose, not affecting
performance ............ 1 .. Suggest repair or replacement.
Burned out .............. A ............ Require replacement.
Intermittent ............ A ............ Require replacement.
Missing ................. C ............ Require replacement.
Seized in socket ........ A .. Require repair or replacement.
Terminal broken ......... A .. Require repair or replacement.
Terminal burned, affecting
performance ............ A .............. ( 2) Require repair
or replacement.
Terminal burned, not
affecting performance .. 2 .............. ( 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.