service DODGE RAM 1999 Service Service Manual

SERVICE VALVE LOCATIONS
For service valve locations, see SERVICE VALVE LOCATIONS
(CARS) or SERVICE VALVE LOCATIONS (TRUCKS & VANS) table.
SERVICE VALVE LOCATIONS (CARS)









\









\









\









\









\









\









\








Vehicle High Low
Chrysler Corp.
Avenger & Sebring Coupe .................... ( 1) ........... ( 2)
Concorde, Intrepid, LHS & 300M
2.7L ...................................... ( 3) ........... ( 4)
3.2L & 3.5L ............................... ( 5) ........... ( 6)
Breeze, Cirrus & Stratus ................... ( 7) ........... ( 4)
Neon ....................................... ( 7) ........... ( 4)
Sebring Convertible ........................ ( 7) ........... ( 4)
Ford Motor Co.
Continental ................................ ( 9) .......... ( 10)
Contour, Cougar & Mystique
2.0L Engine ............................... ( 7) .......... ( 11)
2.5L Engine ............................... ( 7) .......... ( 12)
Crown Victoria, Grand Marquis & Town Car ... ( 7) .......... ( 13)
Escort & Tracer ............................ ( 14) ......... ( 10)
Mustang .................................... ( 7) .......... ( 12)
Sable & Taurus ............................. ( 8) .......... ( 11)
General Motors
"C" Body ................................... ( 3) .......... ( 15)
"E" & "K" Bodies ........................... ( 3) .......... ( 15)
"F" Body ................................... ( 9) ........... ( 4)
"G" Body ................................... ( 3) .......... ( 15)
"H" Body ................................... ( 7) .......... ( 12)
"J" Body ................................... ( 7) .......... ( 12)
"M" Body ................................... ( 9) ........... ( 4)
"N" Body ................................... ( 9) ........... ( 4)
"S" Body ................................... ( 9) ........... ( 4)
"V" Body ................................... ( 9) ........... ( 4)
"W" Body ................................... ( 9) ........... ( 4)
"Y" Body ................................... ( 3) .......... ( 12)
"Z" Body ................................... ( 7) .......... ( 15)
( 1) - On high-side liquid line, between receiver-drier and evaporator.
( 2) - On low-side hose between evaporator and compressor.
( 3) - On high-side liquid line.
( 4) - On low-side suction line.
( 5) - On top of compressor manifold.
( 6) - On compressor manifold, closest to compressor clutch.
( 7) - On high-side line, between compressor and condenser.
( 8) - On extension of high-side line, between condenser and
evaporator.
( 9) - On high-side line (or extension), near condenser.
( 10 ) - On low-side line (or extension), near accumulator.
( 11 ) - On low-side line, between the evaporator and
accumulator/receiver-drier.
( 12 ) - On low-side line, between acumulator/receiver-dryer and
compressor.
( 13 ) - On acumulator/receiver-drier.
( 14 ) - On high-side line, near condenser.
( 15 ) - On low-side line, between orifice tube and evaporator.









\









\









\









\









\









\









\








SERVICE VALVE LOCATIONS (TRUCKS & VANS)

Fig. 7: Locating Service Valves (Caravan, Town & Country, & Voyager)
Courtesy of chrysler corp.

Fig. 8: Locating Service Valves (Windstar)
Courtesy of ford motor co.
SERVICE EQUIPMENT

Because R-134a is not interchangeable with R-12, separate
sets of hoses, gauges, and recovery/recycling equipment are required
to service vehicles. This is necessary to avoid cross-contamination
and damaging system.
All equipment used to service systems using R-134a must meet
SAE standard J2210. The service hoses on the manifold gauge set must
have manual (turn wheel) or automatic back-flow valves at the service
port connector ends. This will prevent refrigerant from being released
into the atmosphere.
For identification purposes, R-134a service hoses must have a
Black stripe along their length and be clearly labeled SAE J2196/134a.
The low pressure test hose is Blue with a Black stripe. The high-side
test hose is Red with a Black stripe. The center test hose is Yellow,
or White, with a Black stripe.
NOTE: Refrigerant R-12 service hoses will ONLY be labeled SAE
J2196.
All R-134a manifold gauge sets can be identified by one or
all of the following:
* Labeled FOR USE WITH R-134a on set.
* Labeled HFC-134 or R-134a on gauge face.
* Light Blue color on gauge face. In addition,
pressure/temperature scales on R-134a gauge sets are
different from R-12 manifold gauge sets.
MANIFOLD GAUGE SET
A manifold gauge set is used to determine the system's high-
side and low-side pressures, correct refrigerant charge, and operating
efficiency. High (discharge) and low (suction) pressures must be
compared to determine system operation. Manifold gauge sets for the 2
refrigerant types are basically the same except for fittings at ends
of hoses. Fittings are different to ensure connection only to
appropriate refrigerant system.
Low-Side Gauge
Low-side gauge, which may have a Blue identifying feature, is
used to measure low-side (suction) pressure. Low-side gauge is also
called a compound gauge because it can measure pressure and vacuum.
Pressure scale ranges from 0 to 150 psi; vacuum scale ranges from 0 to
30 in. Hg.
High-Side Gauge
High-side gauge, which may have a Red identifying feature, is
used to measure high-side (discharge) pressure. Gauge scale ranges
from 0 to 500 psi.
CONNECTING GAUGE SET
NOTE: R-134a quick disconnect service couplings are connected in
the same sequence as Schrader-type service valves.
Schrader-Type Valves
1) Put on safety goggles, and cover vehicle's fender. Slowly
remove protective caps from Schrader valves to check for leaky valves.
CAUTION: Ensure hand valves on manifold gauge set and the hose-end
shutoff valves are closed before attaching test hoses to
Schrader valves.

2) Ensure service hoses are equipped with valve core
depressor to match Schrader valve. If not, install special adapters
for this purpose. If the high-side service hose connector will not fit
on high-side Schrader valve, a special adapter must be used. See
SPECIAL VALVE CONNECTORS.
3) Ensure both manifold gauge set hand valves are closed.
Connect low-side service hose to low-side (suction) service valve, and\
finger tighten connections. Connect high-side service hose to high-
side (discharge) service valve, and finger-tighten connections.
NOTE: After test gauges are installed, test hoses must be purged of
all air before proceeding with testing.
PURGING TEST HOSES
1) Ensure high-side and low-side hoses are properly connected
to service valves, and all hose connections are tight. Place a clean
shop towel over end of center service hose.
2) Purge high-side test hose by opening hand valve on high-
side gauge for 3-5 seconds. This allows the system's refrigerant to
force air through test hoses and out of center service hose into the
shop towel. Immediately close high-side gauge hand valve.
3) Purge low-side test hose in the same manner using hand
valve of low-side gauge. Close hand valve after 3-5 seconds. Purging
of test hoses is now complete, and system is ready for testing.
NOTE: If manifold gauge set is to be used in conjunction with
refrigerant recovery/recycling equipment, use instructions
provided with the recovery/recycling equipment to properly
purge test hoses.
STABILIZING A/C SYSTEM
1) Once manifold gauge set is attached to system and test
hoses have been purged, the system is ready for testing. Place all
test hoses, gauge set and other equipment away from all moving parts
of engine.
2) Start engine, and turn A/C controls to maximum cooling
position (full cold or MAX A/C). Set blower on high speed. Open doors
and/or windows. Operate system for 5-10 minutes. System should now be
stabilized and ready for test readings.
PRESSURE-TEMPERATURE RELATIONSHIP
A refrigerant, when confined in an enclosed space, increases
in pressure as the temperature increases. Conversely, if the
temperature is lowered, the pressure also decreases.
Depending on temperature, a corresponding pressure will exist
in such an enclosed space. For example, at 70
F (21.1C) a gauge will
indicate about 71.0 psi (5.0 kg/cm). The R-134a PRESSURE- TEMPERATURE
RELATIONSHIP table shows this relationship.
R-134a PRESSURE-TEMPERATURE RELATIONSHIP









\









\









\









\









\









\









\








Temperature F (C) ( 1) psi (kg/cm)
20 (-6.7) ................................................. 18 (1.3\
)
30 (-1.1) ................................................. 26 (1.8\
)
40 (4.4) .................................................. 35 (2.5\
)
50 (10.0) ................................................. 45 (3.2\
)
60 (15.6) ................................................. 57 (4.0\
)

70 (21.1) ................................................. 71 (5.0\
)
80 (26.7) ................................................. 87 (6.1\
)
90 (32.2) ................................................ 104 (7.3\
)
100 (37.8) ............................................... 124 (8.7\
)
110 (43.3) .............................................. 147 (10.3\
)
120 (48.9) .............................................. 171 (12.0\
)
130 (54.4) .............................................. 199 (14.0\
)
140 (60.0) .............................................. 229 (16.1\
)
150 (65.6) .............................................. 263 (18.5\
)
160 (71.1) .............................................. 300 (21.1\
)
(1) - Pressure readings are provided as a general guideline and may
not represent actual readings.









\









\









\









\









\









\









\








PRESSURE GAUGE READINGS
The pressure gauge readings shown represent an expansion
valve type system using a Nippondenso 10-cylinder compressor. See
Figs. 9 -17. Gauge indications will vary depending on system
configuration and compressor application.
Temperature and humidity, as well as other factors, affect
pressure gauge readings. Compared to R-12 systems, pressure readings
on R-134a systems are generally lower for low-side pressure and higher
for high-side pressure. Pressure gauge readings should be used only as
a guide.
NOTE: For additional information, see latest MITCHELL AUTOMOTIVE
AIR CONDITIONING BASIC SERVICE TRAINING MANUAL.
Fig. 9: Normally Functioning R-134a A/C System

"U" Series ............ Condenser Outlet ................... N/A
(1) - In evaporator (liquid) inlet line, between service valves, above
accumulator.
( 2) - Cutlass and Malibu only.
( 3) - In evaporator (liquid) inlet line, between high-side service
valve and evaporator.









\









\









\









\









\









\









\








JEEP
NOTE: On Cherokee and Grand Cherokee, fixed orifice tube is located
in the liquid line. If the fixed orifice tube is faulty or
plugged, the liquid line and orifice tube must be replaced as
an assembly.
Removal & Installation (Cherokee & Grand Cherokee)
Disconnect battery negative cable. Discharge A/C system,
using approved refrigerant recovery/recycling equipment. Disconnect
liquid line retaining clips. Disconnect liquid line from evaporator
inlet and condenser outlet tubes. Cover open refrigerant fittings to
protect from moisture and dirt. Remove liquid line and orifice tube.
To install, reverse removal procedure. Evacuate, charge, and leak test
A/C system. Ensure A/C system operates properly.
Removal & Installation (Wrangler)
1) Disconnect battery negative cable. Discharge A/C system,
using approved refrigerant recovery/recycling equipment. Disconnect
liquid line at condenser outlet tube. Cover open refrigerant fittings
to protect from moisture and dirt.
2) Using needle nose pliers, remove fixed orifice tube from
condenser outlet tube. Note fixed orifice tube orientation for correct
installation. To install, reverse removal procedure. Ensure fixed
orifice tube is positioned correctly. Evacuate, charge, and leak test
A/C system. Ensure A/C system operates properly.
REFRIGERANT RECOVERY/RECYCLING
Refrigerant recovery/recycling equipment is used to remove
refrigerant from vehicle's A/C system without polluting atmosphere. To
remove and recycle refrigerant, ALWAYS follow instructions provided
with the refrigerant recovery/recycling equipment being used.
The removed refrigerant is filtered, dried and stored in a
tank within the recovery/recycling equipment until it is ready to be
pumped back into the vehicle's A/C system.
NOTE: Separate sets of hoses, manifold gauge set and refrigerant
recovery/recycling equipment MUST be used for R-12 and R-134a
systems. DO NOT mix R-12 and R-134a refrigerants, as their
refrigerant oils and desiccants are NOT compatible.
CHRYSLER CORP.
Manufacturer recommends using refrigerant recovery/recycling
equipment which meets SAE standard J1991 or J2210. Always follow
instructions provided with the recovery/recycling equipment being
used.
FORD MOTOR CO.
1) Connect hoses from Recovery/Recycling/Charging Center
(023-00150) to high-side and low-side service valves. See SERVICE

VALVE LOCATIONS under SYSTEM SERVICE VALVES.
2) Turn equipment on and recover refrigerant according to
equipment manufacturer's operating instructions. Allow equipment to
operate until refrigerant is recovered. Close inlet valve (if
equipped) on refrigerant recovery/recycling/charging center and turn
equipment off.
NOTE: On some applications, refrigerant recovery/recycling/charging
center will automatically shut off through the use of a low
pressure switch. On other applications, refrigerant
recovery/recycling/charging center must be manually shut
off.
3) Allow A/C system to remain closed for about 2 minutes
while observing vacuum pressure readings. If vacuum pressure reading
increases, repeat step 2) until vacuum pressure readings remain stable
for 2 minutes. If vacuum pressure readings remain stable for 2
minutes, disconnect hoses from service ports and perform required A/C
system repairs.
GENERAL MOTORS
Manufacturer recommends using A/C Refrigerant Recovery,
Recycling And Recharging (ACR4) System (J-39500). The ACR4 system ha\
s
one filtering cycle during recovery plus an automatic multiple pass
filtering during evacuation cycle. Follow manufacturer's instructions
provided with ACR4 equipment being used.
JEEP
Manufacturer recommends using refrigerant recovery/recycling
equipment which meets SAE standard J1991 or J2210. Always follow
instructions provided with the recovery/recycling equipment being
used.
FLUSHING A/C SYSTEM
There is considerable controversy over the question of
whether or not to flush A/C systems or how to go about it. Before CFCs
were classified as harmful to the environment, it was a common
practice to open flush contaminants from a system. The waste fluid was
vented to the atmosphere. This practice is now ILLEGAL and can no
longer be used.
Most OEMs don't recommend A/C system flushing. They recommend
replacing the defective component and installing a liquid line (in-
line) filter ahead of the expansion valve or orifice tube. Ford Motor
Company is one exception to this rule.
CHRYSLER CORP.
Information is not available from manufacturer.
FORD MOTOR CO.
NOTE: DO NOT flush accumulator/receiver-drier, muffler, hoses and
thermal expansion valve/fixed orifice tube as residual
flushing agent cannot be completely removed from these
components. These components are generally replaced after A/C
system contamination. Hoses can be reused, unless they are
clogged with debris. Only flush evaporator core and condenser
core, and metal inlet and outlet lines.

Fig. 23: Temporary Pancake Filter
Courtesy of ford motor co.
GENERAL MOTORS
Information is not available from manufacturer.
JEEP
Information is not available from manufacturer.
EVACUATING A/C SYSTEM
CAUTION: DO NOT operate A/C compressor during evacuation procedure or
with vacuum applied to A/C system. Compressor may be
damaged.
CHRYSLER CORP.
Avenger 2.0L & Sebring Coupe 2.0L
1) Ensure all manifold gauge set valves are closed. Connect
manifold gauge set service valves. Connect vacuum pump adapter to
vacuum pump. Connect manifold gauge set Yellow hose to vacuum pump
adapter.
2) Fully open manifold gauge set low-pressure valve and
adapter valve, and start vacuum pump. Operate vacuum pump for about 10
minutes until low-side vacuum reading is 29.5 in. Hg or more. Turn
vacuum pump off and observe vacuum gauge.
3) If A/C system maintains specified vacuum for 5 minutes,
system is okay. If A/C system cannot get to or maintain specified
vacuum for 5 minutes, ensure connections are tight and repeat
evacuation. If A/C system still does not maintain specified vacuum,
check for defective vacuum pump or leak in A/C system or gauge set.
See LEAK TESTING. Repair or replace components as necessary.

Avenger 2.5L & Sebring Coupe 2.5L
Connect approved recovery/recycling equipment to vehicle.
Evacuate A/C system using recovery/recycling equipment according to
manufacturer's instructions.
Dakota, Durango, Ram Pickup & Ram Van/Wagon
1) Connect approved recovery/recycling equipment and manifold
gauge set. Fully open manifold gauge set low-side and high-side
valves, and start vacuum pump. Operate vacuum pump until low-side
vacuum reading of 26 in. Hg or more. Close all valves and turn vacuum
pump off. Observe vacuum gauge and go to next step.
2) If A/C system maintains specified vacuum for 5 minutes,
restart vacuum pump, open low-side and high-side valves, and evacuate
system for an additional 10 minutes. Close all valves. Turn vacuum
pump off and disconnect pump.
3) If A/C system cannot get to or maintain specified vacuum,
check for a defective vacuum pump or a leak in A/C system or gauge
set. See LEAK TESTING. Repair or replace components as necessary.
All Other Models
1) Connect approved recovery/recycling equipment and manifold
gauge set to vacuum pump. Fully open manifold gauge set suction and
discharge valves, and start vacuum pump. Operate vacuum pump at least
45 minutes with a low-side vacuum reading of 26 in. Hg or more (28 in.
Hg or more on Neon). Close all valves. Turn vacuum pump off and
observe vacuum gauge.
2) If A/C system maintains specified vacuum for 30 minutes,
open all valves, start vacuum pump and operate for an additional 10
minutes. Close all valves. Turn vacuum pump off and disconnect pump.
If A/C system cannot get to or maintain specified vacuum for 30
minutes, check for a defective vacuum pump or leak in A/C system or
gauge set. See LEAK TESTING. Repair or replace A/C system components
as necessary.
FORD MOTOR CO.
1) If using approved Recovery/Recycling/Charging Center (023-\
00150) connect to high-side and low-side service valves. See SERVICE
VALVE LOCATIONS under SYSTEM SERVICE VALVES. Connect manifold gauge
set center hose to vacuum pump.
2) Open both valves on manifold gauge set. Operate vacuum
pump until low-side vacuum reading is at least 29.5 in. Hg (as close
to 30 in. Hg as possible). Operate vacuum pump for at least 45
minutes.
3) Close both valves on manifold gauge set. Turn off vacuum
pump. Observe low-side gauge. Any loss of vacuum in 5 minutes
indicates a system leak. Perform leak testing procedure. See LEAK
TESTING. Repair system as necessary and repeat evacuation procedure.
GENERAL MOTORS
Manufacturer recommends using A/C Refrigerant Recovery,
Recycling And Recharging (ACR4) System (J-39500). The ACR4 system ha\
s
one filtering cycle during recovery plus an automatic multiple pass
filtering during evacuation cycle. Follow manufacturer's instructions
provided with ACR4 equipment being used.
JEEP
1) Connect approved recovery/recycling equipment and manifold
gauge set. Fully open manifold gauge set low-side and high-side
valves, and start vacuum pump. Operate vacuum pump until low-side