1999 DODGE RAM air conditioning
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Fig. 24: Electronic Leak Detector
PREPARATION FOR LEAK TESTING
Connect manifold gauge set to air conditioning system. Ensure
low-side and high-side gauge set valves are closed. Check system
pressure. It should be at least 50 psi (3.5 kg/cm
). If system is
empty, evacuate A/C system and apply 28 in. Hg of vacuum. If system
holds vacuum for 15 minutes there most likely are no leaks present. If
low, add just enough refrigerant (about 10 ounces) to bring system to
50 psi (3.5 kg/cm
).
Ensure all joints, connections, and fittings are free of oil
dirt and other contaminants. Using a refrigerant leak detector, check
all refrigerant line connections for leaks. Check condenser and
compressor seal area.
Start engine and allow to idle. Operate A/C system for about
5 minutes. Set A/C controls to outside air, and high blower speed.
Turn A/C on, and open vehicle windows. Turn engine off and wait 2-7
minutes. Refrigerant is heavier than air. Always check for leaks at
bottom of refrigerant lines and components. Refrigerant oil will leak
with refrigerant. Visually check all connections and compressor clutch
area for oil stains. If compressor shaft seal is leaking, a fresh oil
streak will normally be seen on underside of hood, above compressor
clutch.
Always perform leak testing after A/C service. Move
refrigerant leak detector slowly to check for leaks, as leaks will not
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be detected if leak testing is performed too quickly.
BUBBLE DETECTOR LEAK TESTING PROCEDURE
This leak detection method is recommended when it is
impossible or difficult to determine the exact location of the leak
using other methods. Although commercial bubble detectors are more
effective, household soap solutions may be used.
Using the dauber that comes with the commercial soap
solution, apply the solution to all joints, connections, fittings or
controls where a leak might be suspected. If high-suds household
solutions are used, apply them with a small brush. Wherever bubbles
form, leaks are present and must be repaired. check the entire system
as there may be more than one leak.
ELECTRONIC LEAK TESTING PROCEDURE
NOTE: Some electronic leak detectors will function on only R-12
systems or on only R-134a systems, and some will function on
both R-12 and R-134a systems. Familiarize yourself with the
tester being used and know what type of system you are leak
testing.
Electronic leak detectors should be used in well ventilated
areas. Avoid using them around explosive gases. Always follow
manufacturer's instructions for the specific tester being used. If
none are available, proceed as follows:
1) Turn all controls and detector sensitivity knob to OFF
position or zero setting. Connect leak detector to an approved source
of power. Turn switch ON, and allow unit to warm up for approximately
5 minutes.
2) Check operation of tester by positioning probe in a
reference source where refrigerant is known to be present in small
amounts. Adjust controls and sensitivity knob until detector reacts
properly. Move probe away from refrigerant source and the reaction
should stop. If it continues, adjust the sensitivity knob to a lower
setting.
3) When tester reacts properly, leak test air conditioning
system by moving probe UNDER all components, fittings and connections.
Keep the probe moving. To check evaporator insert probe into drain
tube opening or a heater duct. DO NOT allow probe to contact
refrigerant or refrigerant oil. When leaks are found, repair them as
necessary. Keep in mind that there may be more than one leak.
DYE SOLUTION LEAK TESTING PROCEDURES
CAUTION: Dye-charged refrigerant cans are available to be used as
internal leak detectors. The use of this type of solution may
void some manufacturer's warranties. Be sure to check with
the A/C system manufacturer concerning the use of dye-charged
leak detectors. Dyes which work in R-12 systems will not work
in R-134a systems.
The following procedure is for introducing a dye solution,
not dye-charged refrigerant, into A/C system.
1) Connect manifold gauge set to air conditioning system in a
normal manner. Remove center hose from manifold gauge set, and replace
it with a short piece (6" long) of 1/4" tubing using two 1/4" flare
nuts. Connect a container of dye solution to the tubing.
2) Connect one end of gauge set center hose to dye solution
container. Connect a container of refrigerant to the other end of the
hose. Operate engine at idle speed. Set the air conditioning system
for maximum cooling. Slowly open the low-side hand valve to allow the
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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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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
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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
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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 473 of 1691
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.