For 1990-2009 cars

Step | Action | Value | 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 | 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)? | -- | Go to Step 7 | Go to Step 3
3 | 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 4 | Go to Step 5
4 | 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? | -- | Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D | Go to Step 5
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.

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

• | The discharge line is hot.

• | The suction line is cool.

Do the listed conditions exist?

--

Go to Step 7

Go to Step 6

6 | 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 within Zone A on the A/C Pressure-Zone Classification Chart in the A/C System Performance Test. 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 8

Go to Air Temperature Malfunction

7 | The A/C system may be undercharged.

1. Leak test 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?

--

Go to Step 14

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8 | The A/C system may be contaminated. View the J 43600 ACR 2000 information screen for detection of foreign gases in the A/C system. Do foreign gases exist? | -- | Go to Step 9 | Go to Step 10
9 |

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?

--

Go to Step 14

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10 | 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 15

Go to Step 11

11 | The A/C system may contain too much refrigerant oil.

Note: Operate the A/C system on low, in order to enhance oil flow to the high side of the system.

1. Operate the A/C system with the engine at idle speed and the blower speed on low for approximately 15 minutes.
2. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging.
3. Measure the oil recovered by the J 43600 .

Was the amount greater than the specified value?

60 ml (2 oz)

Go to Step 12

Go to Step 13

12 | Recharge the A/C system but do not add the amount of oil recovered by the J 43600 . Refer to Refrigerant Recovery and Recharging. Are the repairs complete? | -- | Go to Step 14 | --
13 | Recharge the A/C system but do not add the amount of oil recovered by the J 43600 . Refer to Refrigerant Recovery and Recharging. Are the repairs complete? | -- | Go to Step 14 | --
14 |

1. Record the low and high side pressures and the I/P panel 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 panel outlet temperatures within specifications?

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Go to Step 15

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

15 | Operate the system in order to verify the repair. Did you find and correct the condition? | -- | System OK | Go to Symptoms - HVAC Systems - Manual