1988 JEEP CHEROKEE air conditioning

ALTITUDE PRESSURE VARIATIONS
ALTITUDE PRESSURE VARIATIONS








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Altitude (Ft. Absolute Pressure Gauge Altitude
Above Sea Level) of Atmosphere(psi) Correction (1) (psi)
0 ...................... 14.7 ........................ 0
1000 ................... 14.2 ..................... -0.5
2000 ................... 13.7 ..................... -1.0
3000 ................... 13.2 ..................... -1.5
4000 ................... 12.7 ..................... -2.0
5000 ................... 12.2 ..................... -2.5
6000 ................... 11.7 ..................... -3.0
7000 ................... 11.3 ..................... -3.4
8000 ................... 10.9 ..................... -3.8
9000 ................... 10.5 ..................... -4.2
10,000 ................. 10.1 ..................... -4.6
(1) - Subtract correction shown from gauge readings.









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ALTITUDE VACUUM VARIATIONS








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Altitude (Ft. Complete Vacuum Gauge Altitude
Above Sea Level) (In. Hg) Correction (In. Hg)
0 ...................... 29.92 ....................... 0
1000 ................... 28.92 .................... +1.0
2000 ................... 27.82 .................... +2.1
3000 ................... 26.82 .................... +3.1
4000 ................... 25.82 .................... +4.1
5000 ................... 24.92 .................... +5.0
6000 ................... 23.92 .................... +6.0
7000 ................... 23.02 .................... +6.9
8000 ................... 22.22 .................... +7.7
9000 ................... 21.32 .................... +8.6
10,000 ................. 20.52 .................... +9.4
(1) - Add correction shown to gauge readings.









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OPERATIONAL TEST GAUGE READINGS
Normal System Operating Pressures (PSI) (1)









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Low Side Gauge High Side Gauge
Application (Suction) (Discharge)
Thermostatic Switch .... 5-24 .................. 208-250
(1) - Pressure readings given are for a system in good
operating condition, at sea level and an ambient
temperature of 80
F (27C).








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A/C SYSTEM PERFORMANCE CHECK TABLE
AIR CONDITIONING SYSTEM PERFORMANCE CHECK








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PERFORM TESTS: SHOULD BE: IF:








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Temperature Check Temperature Check Is

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.

of caliper.
Piston sticking ......... A ........... Require rebuilding or
replacement of caliper.
Slide mechanism
sticking ............... A ... Require repair or replacement
of slide mechanism.
(1) - Only required if the hydraulic system must be opened.
( 2) - Seized is defined as a bleeder screw that cannot be
removed after a practical attempt at removing. Only
required if the hydraulic system must be opened.









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CONTROLLERS
See ELECTRONIC CONTROLLERS .
DIGITAL RATIO AXLE CONTROLLERS AND BUFFERS (DRAC AND DRAB)
DIGITAL RATIO AXLE CONTROLLER AND BUFFER INSPECTION








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Condition Code Procedure
Connector broken ........ A .. Require repair or replacement.
Connector (Weatherpack
type) leaking .......... A .. Require repair or replacement.
Connector melted ........ A ........ ( 1) Require replacement.
Connector missing ....... C ............ Require replacement.
Missing ................. C ............ Require replacement.
Output signal incorrect . B .. 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 replacement of part.
( 2) - Determine cause and correct prior to repair or
replacement of part.









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DISABLE SWITCHES
See SWITCHES.
DRUMS
Determine the need to recondition based upon individual drum
conditions that follow. Friction material replacement does not require
drum reconditioning unless other justifications exist. DO NOT
recondition new drums unless they are being pressed or bolted onto an
existing hub. It is not necessary to replace drums in axle sets.
However, when replacing or reconditioning a drum due to the conditions
that follow, you may suggest reconditioning of the other drum on the

Wear indicator device
(mechanical) contacts
rotor .................. .. ......... (6) Further inspection
required.
Worn close to minimum
specifications ......... 1 ........ ( 7) Suggest replacement.
Worn to, or below minimum
specifications ......... B ............ Require replacement.
( 1) - Identify and repair cause of contamination prior to
replacing friction material.
( 2) - When reconditioning or replacing drums or rotors,
replacement of friction material may be suggested
depending on the severity of the grooves or ridges.
( 3) - Some vehicles use pads that are tapered by design. Refer
to specific vehicle application. If not normal, require
replacement of pads and correction of cause.
( 4) - Uneven pad thickness is normal on some vehicles. Refer to
specific vehicle applications.
( 5) - The pad wear indicator light may come on due to other
electrical problems.
( 6) - Explain to the customer that the purpose of the wear
indicator is to alert him or her to check for friction
wear. Wear indicators may be bent or broken. Therefore,
the friction material must be measured. The need for
friction material replacement is determined based upon
the conditions stated in this section. Periodic inspection
is suggested.
( 7) - When the part appears to be close to the end of its useful
life, replacement may be suggested.









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G SENSORS
See ACCELEROMETERS .
HOSES
HOSE 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.
Blistered ............... B ............ Require replacement.
Fitting threads damaged . A .. Require repair or replacement.
Fitting threads stripped
(threads missing) ...... A ............ Require replacement.
Incorrectly secured ..... B ................. Require repair.
Inner fabric
(webbing) cut .......... B ............ Require replacement.
Leaking ................. A ............ Require replacement.
Missing ................. C ............ Require replacement.
Outer covering is cracked
to the extent that
inner fabric of hose

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

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)

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 & 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.
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.

performs its intended
function ............... A ............ Require replacement.
Weights missing ......... A ............ Require replacement.









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FLUID LEVEL INDICATORS
See DIP STICKS (FLUID LEVEL INDICATORS) .
FLUIDS AND LUBRICANTS
FLUID AND LUBRICANT INSPECTION








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Condition Code Procedure
Application incorrect ... B ........ ( 1) Require replacement.
At service interval ..... 3 ............ Suggest replacement.
Beyond service interval . 3 ............ Suggest replacement.
Burned .................. .. ......... ( 2) Further inspection
required.
Contaminated, for example,
fluid other than hydraulic
fluid present .......... A or B .... ( 3)( 4) Require service.
Exceeding service
interval ............... 3 ............ Suggest replacement.
Hydraulic fluid
incorrect .............. B ............ ( 5) Require service.
Level incorrect ......... B ..... Require correction of fluid
level.
Near service interval ... 3 ............ Suggest replacement.
Rubber master cylinder
cover gasket distorted
and gummy .............. A ............ ( 3) Require service.
Varnished ............... .. ......... ( 6) Further inspection
required.
( 1) - Determine and correct cause.
( 2) - Fluid that is burned indicates a serious problem.
Determine and correct the cause.
( 3) - If a fluid other than hydraulic fluid is present in the
hydraulic system which DOES affect the rubber parts, the
required service is to: 1) remove all components having
rubber parts from the system, 2) flush lines with
denatured alcohol or hydraulic cleaner, 3) repair or
replace all components having rubber parts, and 4) bleed
and flush with correct hydraulic fluid. (Code A)
( 4) - If a fluid other than hydraulic fluid is present in the
hydraulic system which DOES NOT affect the rubber parts,
the required service is to flush and fill with the
correct hydraulic fluid. (Code B)
( 5) - If a fluid other than specification hydraulic fluid is
present in the hydraulic system, the required service
is to flush and fill with the correct hydraulic fluid.
( 6) - Fluid that is varnished may indicate a serious problem.
Determine and correct the cause.









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FLYWHEELS
NOTE: Clutch disc replacement does not necessitate flywheel
reconditioning, unless other conditions justify the
reason to do so.