For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
DEFINITION: The high and low side pressures may be normal or slightly less than normal.

• | Air Delivery Concern

• | Slight Refrigerant Under Charge

• | Refrigerant Contamination

1 | Were you sent here from the A/C System Performance Test? | Go to Step 2 | Go to Air Conditioning (A/C) System Performance Test
2 | Did the customer mention that the A/C system output temperatures are good at first, but then turn warm during extended drives? | Go to Step 3 | Go to Step 4
3 | Increase engine speed to 1,500 RPM. During extended operation of the A/C system, does the low side pressure decrease? | Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D | Go to Step 4
4 | Refer to the pressures recorded during the A/C system performance test. Warning: Refer to Moving Parts and Hot Surfaces Warning in the Preface section. Inspect for the following conditions:

• | The high side pressure is slightly greater than the specified pressure ranges in the A/C System performance Table but still near Zone A on the A/C Pressure-Zone Classification Chart. Refer to Air Conditioning (A/C) System Performance Test.

• | The discharge line is very hot.

• | The suction line is cool.

Do the listed conditions exist?

Go to Step 7

Go to Step 5

5 | Refer to the pressures recorded during the A/C system performance test. Inspect for the following conditions:

• | The low side pressure is slightly lower than the specified pressure ranges but still near Zone A on the A/C Pressure-Zone Classification Chart. Refer to Air Conditioning (A/C) System Performance Test.

• | The discharge line is warm-to-hot.

• | The suction line is cool-to-warm.

Do the listed conditions exist?

Go to Step 6

Go to Too Hot in Vehicle

6 | The A/C system may be undercharged of refrigerant.

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

Is the repair complete?

Go to Step 11

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7 | 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? | Go to Step 8 | Go to Step 9
8 |

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

Is the repair complete?

Go to Step 11

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9 | 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?

Go to Step 11

Go to Step 10

10 |

1. Record the low and high side pressures and the instrument panel (I/P) outlet air temperature.
2. Compare the panel outlet temperatures and pressure 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?

Go to Step 11

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

11 | Operate the system in order to verify the repair. Have the concerns been eliminated? | System OK | Go to Symptoms - HVAC Systems - Automatic