DEFINITION: The high and low side pressures may be normal or slightly less than normal.

Were you sent here from the A/C System Performance Test?

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Go to Step 2

Go to Air Conditioning (A/C) System Performance Test

Refer to the panel air outlet temperatures recorded during the A/C system performance test.

Does the discharge air temperature between the right and left center panel outlets vary by more than 4°C (5°F)?

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Go to Step 7

Go to Step 3

Did the customer mention that the A/C system output temperatures are good at first, but then turn warm during extended drives?

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Go to Step 4

Go to Step 5

Increase engine speed to 2,000 RPM.

During extended operation of the A/C system, does the low side pressure decrease, possibly accompanied by heavy frost on the liquid line between the expansion device and the evaporator?

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Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 5

Refer to the pressures recorded during the A/C system performance test.

Inspect for the following conditions:

Warning: Refer to Moving Parts and Hot Surfaces Warning in the Preface section.

Do the listed conditions exist?

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Go to Step 7

Go to Step 6

Refer to the pressures recorded during the A/C system performance test.

Inspect for the following conditions:

Do the listed conditions exist?

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Go to Step 8

Go to Air Temperature Malfunction

The A/C system may be undercharged.

1. Leak test the A/C system. Refer to Leak Testing.
2. Recharge the A/C system to specifications. Refer to Refrigerant Recovery and Recharging.

Is the repair complete?

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Go to Step 13

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The A/C system may be contaminated.

View the J 43600 ACR 2000 Air Conditioning Service Center information screen for detection of foreign gases in the A/C system.

Do foreign gases exist?

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Go to Step 9

Go to Step 10

1. Evacuate the A/C system to a scavenging tank. Refer to Refrigerant Recovery and Recharging.
2. Recharge the A/C system to specifications.

Is the repair complete?

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Go to Step 13

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The A/C system may contain too much moisture or air.

1. Evacuate and recharge the A/C system to specifications. Refer to Refrigerant Recovery and Recharging.
2. Operate the A/C system and inspect the panel outlet air temperatures. Refer to Air Conditioning (A/C) System Performance Test.

Are the panel outlet temperatures within the specified ranges of the A/C Performance Test Table?

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Go to Step 14

Go to Step 11

Note: Review the vehicles A/C repair history. If the vehicle history shows multiple A/C repairs and is suspected of improper polyalkylene glycol (PAG) oil balancing in the previous repairs, perform the following procedure:

1. Drain all of the PAG oil drain bottle on the J 43600 .
2. Flush the A/C system. Refer to Flushing.

Was more than the total system capacity of refrigerant oil recovered from the J 43600 oil drain bottle?

148 ml (5 oz)

Go to Step 12

Go to Step 12

1. Add the specified amount of refrigerant oil. Refer to Refrigerant System Capacities.
2. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging.

Are the actions complete?

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Go to Step 13

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1. Record the low and high side pressures and the instrument panel (I/P) outlet air temperature.
2. Compare the panel outlet temperatures to those listed in the A/C System Performance Chart. Refer to Air Conditioning (A/C) System Performance Test.

Are the high and low side pressures and I/P outlet temperatures within specifications?

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Go to Step 14

Go to Air Conditioning (A/C) System Performance Test

Operate the system in order to verify the repair.

Did you find and correct the condition?

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System OK

Go to Symptoms - HVAC Systems - Manual