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Dodge Dakota (ND). Manual - part 1295

CAUTION: Do not overcharge the refrigerant system. Overcharging will cause excessive compressor head
pressure and can cause compressor noise and A/C system failure.

DIAGNOSIS AND TESTING

REFRIGERANT SYSTEM LEAKS

WARNING: R-134a service equipment or vehicle A/C system should not be pressure tested or leak tested
with compressed air. Mixture of air and R-134a can be combustible at elevated pressures. These mixtures
are potentially dangerous and may result in fire or explosion causing property damage, personal injury or
death.
Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and throat.
Use only approved service equipment meeting SAE requirements to discharge R-134a system. If accidental
system discharge occurs, ventilate work area before resuming service.

If the A/C system is not cooling properly, determine if the refrigerant system is fully charged with R-134a. This is
accomplished by performing a system Charge Level-Check or Fill. If while performing this test A/C liquid line pres-
sure is less than 345 kPa (50 psi) proceed to System Empty procedure. If liquid line pressure is greater than 345
kPa (50 psi) proceed to System Low procedure. If the refrigerant system is empty or low in refrigerant charge, a
leak at any line fitting or component seal is likely. A review of the fittings, lines and components for oily residue is
an indication of the leak location. To detect a leak in the refrigerant system, perform one of the following procedures
as indicated by the symptoms.

SYSTEM EMPTY

1. Evacuate the refrigerant system to the lowest degree of vacuum possible (approximately 28 in Hg.). Determine if

the system holds a vacuum for 15 minutes. If vacuum is held, a leak is probably not present. If system will not
maintain vacuum level, proceed to Step 2.

2. Prepare a 0.284 Kg. (10 oz.) refrigerant charge to be injected into the refrigerant system.

3. Connect and dispense 0.284 Kg. (10 oz.) of refrigerant into the evacuated refrigerant system.

4. Proceed to Step 2 of System Low procedure.

SYSTEM LOW

1. Determine if there is any R-134a refrigerant in the system.

2. Position the vehicle in a wind free work area. This will aid in detecting small leaks.

3. Bring the refrigerant system up to operating temperature and pressure. This is done by allowing the engine to

run for five minutes with the A/C system set to the following:

•

Transmission in Park or Neutral with parking brake set

•

Engine idling

•

Mode control set to the outside air position

•

Blower control set to the high speed position

•

A/C set to the ON position

•

All windows open

CAUTION: A leak detector only designed for R-12 refrigerant will not detect leaks in a R-134a refrigerant
system.

4. Shut the vehicle Off and wait 2-7 minutes. Then use an electronic leak detector that is designed to detect R-134a

refrigerant and search for leaks. Fittings, lines or components that appear to be oily usually indicate a refrigerant
leak. To inspect the A/C evaporator for leaks, insert the leak detector probe into the drain tube opening or an air
outlet. A dye for R-134a is available to aid in leak detection. Use only DaimlerChrysler approved refrigerant dye.

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PLUMBING

STANDARD PROCEDURE

REFRIGERANT SYSTEM SERVICE EQUIPMENT

WARNING: Eye protection must be worn when servicing an A/C refrigerant system. Turn all valves off
(rotate clockwise) on the equipment being used before connecting or disconnecting service equipment from
the refrigerant system. Failure to observe these warnings may result in personal injury or death.

WARNING: Refer to the applicable warnings and cautions for this system before performing the following
operation (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - WARNINGS) and (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - CAUTIONS). Failure to follow the warnings and cautions could result
in possible personal injury or death.

When servicing the A/C system, a R-134a refrigerant
recovery/recycling/charging station that meets SAE
standard J2210 must be used (1). Contact an automo-
tive service equipment supplier for refrigerant recov-
ery/recycling/charging

equipment.

Refer

the

operating instructions supplied by the equipment man-
ufacturer for proper care and use of this equipment.

A manifold gauge set (1) may be needed with some
recovery/recycling/charging equipment. The manifold
gauge set should have manual shut-off valves (2 and
6), or automatic back-flow valves located at the ser-
vice port connector end of the manifold gauge set
hoses (4 and 5). This will prevent refrigerant from
being released into the atmosphere.

PLUMBING

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MANIFOLD GAUGE SET CONNECTIONS

CAUTION: Do not use an R-12 manifold gauge set on an R-134a system. The refrigerants are not compatible
and system damage will result.

RECOVERY/RECYCLING/EVACUATION/CHARGING HOSE – The center manifold hose (Yellow, or White, with
Black stripe) (3) is used to recover, evacuate, and charge the refrigerant system. When the low or high pressure
valves on the manifold gauge set are opened, the refrigerant in the system will escape through this hose.

HIGH PRESSURE GAUGE HOSE – The high pressure hose (Red with Black stripe) (4) attaches to the high side
service port. This service port is located on the A/C liquid line near the radiator cap. On this model, an A/C pressure
transducer is also installed on the liquid line. A/C high-side pressures can be read using a scan tool. Refer to 9 -
Engine Electrical Diagnostics for more information.

LOW PRESSURE GAUGE HOSE – The low pressure hose (Blue with Black stripe) (5) attaches to the low side
service port. This service port is located on the accumulator.

REFRIGERANT SYSTEM RECOVERY

An R-134a refrigerant recovery/recycling/charging sta-
tion (1) that meets SAE standard J2210 must be used
to recover the refrigerant from the R-134a refrigerant
system. Refer to the operating instructions supplied by
the equipment manufacturer for the proper care and
use of this equipment.

REFRIGERANT SYSTEM EVACUATE

NOTE: Special effort must be used to prevent moisture from entering the A/C system oil. Moisture in the oil
is very difficult to remove and will cause a reliability problem with the compressor.

If an A/C compressor designed to use R-134a refrigerant is left open to the atmosphere for an extended period of
time. It is recommended that the refrigerant oil be drained and replaced with new oil or a new A/C compressor be
used. This will eliminate the possibility of contaminating the refrigerant system.

If the refrigerant system has been open to the atmosphere, it must be evacuated before the system can be filled.
Moisture and air mixed with the refrigerant will raise the compressor head pressure above acceptable operating
levels. This will reduce the performance of the A/C system and damage the A/C compressor. Moisture will boil at
near room temperature when exposed to vacuum. To evacuate the refrigerant system:

NOTE: When connecting the service equipment coupling to the line fitting, verify that the valve of the cou-
pling is fully closed. This will reduce the amount of effort required to make the connection.

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PLUMBING

1. Recover the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PRO-

CEDURE - REFRIGERANT SYSTEM RECOVERY).

2. Connect a suitable charging station, refrigerant recovery machine or a manifold gauge set with vacuum pump

and refrigerant recovery equipment (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD
PROCEDURE - REFRIGERANT SYSTEM SERVICE EQUIPMENT).

3. Open the suction and discharge valves and start the vacuum pump. The vacuum pump should run a minimum of

45 minutes prior to charge to eliminate all moisture in system. When the suction gauge reads -88 kPa (- 26 in.
Hg) vacuum or greater for 30 minutes, close all valves and turn off vacuum pump. If the system fails to reach
specified vacuum, the refrigerant system likely has a leak that must be corrected. If the refrigerant system main-
tains specified vacuum for at least 30 minutes, start the vacuum pump, open the suction and discharge valves.
Then allow the system to evacuate an additional 10 minutes.

4. Close all valves. Turn off and disconnect the vacuum pump.

5. Charge the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PRO-

CEDURE - REFRIGERANT SYSTEM CHARGE).

REFRIGERANT SYSTEM CHARGE

NOTE: Always refer to the underhood HVAC Specification Label for the refrigerant fill specification of the
vehicle being serviced.

After all refrigerant system leaks have been repaired and the refrigerant system has been evacuated, a refrigerant
charge can be injected into the system. For the proper amount of the refrigerant charge, refer to the underhood
HVAC Specification Label.

A R-134a refrigerant recovery/recycling/charging station that meets SAE Standard J2210 must be used to charge
the refrigerant system with R-134a refrigerant. Refer to the operating instructions supplied by the equipment man-
ufacturer for proper care and use of this equipment.

CHARGING PROCEDURE

CAUTION: A small amount of refrigerant oil is removed from the A/C system each time the refrigerant sys-
tem is recovered and evacuated. Before charging the A/C system, you MUST replenish any oil lost during
the recovery process. Refer the equipment manufacturer instructions for more information.

1. Evacuate the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PRO-

CEDURE - REFRIGERANT SYSTEM EVACUATE).

2. A manifold gauge set and an R-134a refrigerant recovery/recycling/charging station that meets SAE standard

J2210 should be connected to the refrigerant system.

3. Measure the proper amount of refrigerant and heat it to 52° C (125° F) with the charging station. See the oper-

ating instructions supplied by the equipment manufacturer for proper use of this equipment.

4. Open both the suction and discharge valves, then open the charge valve to allow the heated refrigerant to flow

into the system.

5. When the transfer of refrigerant has stopped, close both the suction and discharge valves.

6. If all of the refrigerant charge did not transfer from the dispensing device, open all of the windows in the vehicle

and set the heating-A/C system controls so that the A/C compressor is engaged and the blower motor is oper-
ating at its lowest speed setting. Run the engine at a steady high idle (about 1400 rpm). If the A/C compressor
does not engage, test the compressor clutch control circuit and repair as required.

7. Open the low-side valve to allow the remaining refrigerant to transfer to the refrigerant system.

WARNING: Take care not to open the discharge (high pressure) valve at this time. Failure to follow this
warning could result in possible personal injury or death.

PLUMBING

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