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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

Caution: Avoid contact with moving parts and hot surfaces while working around a running engine in order to prevent physical injury.

Feel the liquid line before the expansion (orifice) tube.

Is the liquid line cold before the orifice?

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Go to Step 3

Go to Step 8

Feel along the surfaces of the following high side components for a sudden drop in temperature (The high side components should feel warm/hot from the compressor all the way to the orifice.)

Is there an abrupt drop in temperature noted along the surfaces of any of the components listed?

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Go to Step 7

Go to Step 4

Feel the liquid line at the orifice location for extreme cold, possibly accompanied by heavy frost, then feel along the liquid line after the orifice location for warm temperature.

Is the liquid line extremely cold at the orifice location and warm after the orifice location?

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Go to Step 11

Go to Step 5

Feel along the surfaces of the following low side components for a sudden change in temperature.

Is there an abrupt temperature change felt along the surfaces of any of the components listed?

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Go to Step 7

Go to Step 6

Feel along the surfaces of the following low and high side components to compare the overall temperatures of the low and high sides.

Are the overall temperatures of the low and high side components both only mildly warm?

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Go to Step 12

Go to Step 8

1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
2. Repair the restriction from the component, or replace the component which produced an abrupt temperature drop.

Is the repair complete?

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Go to Step 18

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1. Recover the refrigerant and evacuate the system. Refer to Refrigerant Recovery and Recharging .
2. Record the weight of the refrigerant charge which was removed.

Is the weight of the removed refrigerant charge equal to or above the specified value?

0.95 kg (1.65 lb)

Go to Step 9

Go to Step 9

Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .

Is the cooling performance improved?

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Go to Step 18

Go to Step 10

1. Leak test the system. Refer to Leak Testing .
2. Repair any leaks.

Is the repair complete ?

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Go to Step 18

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Replace the orifice tube. Refer to Expansion (Orifice) Tube Replacement .

Is the repair complete?

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Go to Step 18

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1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
2. Disconnect the suction and discharge lines from the compressor. Refer to Suction Hose Replacement and Discharge Hose Replacement .
3. Inspect for the presence of debris on the compressor suction port screen.

Is there debris present on the compressor suction port screen?

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Go to Step 13

Go to Step 17

1. Remove the debris from the suction port screen.
2. Inspect the orifice for damage or debris. Refer to Expansion (Orifice) Tube Replacement .

Is there evidence of damaged or debris?

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Go to Step 15

Go to Step 14

If the orifice does not show any signs of damage or debris:

1. Remove the suction line from the vehicle. Refer to Suction Hose Replacement .
2. Inspect the hose/line for debris by blowing shop air through the hose at one end while covering the other end with a shop towel.
3. Note the amount of debris collected in the shop towel.

Is there a large amount of debris collected in the shop towel?

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Go to Step 16

Go to Step 17

1. Replace the orifice tube. Refer to Expansion (Orifice) Tube Replacement .
2. If the orifice tube was plugged or nearly plugged, note the type of debris present.
3. If metal flakes (chips) are present, replace the A/C compressor. Refer to Air Conditioning Compressor Replacement .
4. If a brown/black residue is present, replace the accumulator. Refer to Air Conditioning Accumulator Replacement .

Is the repair complete?

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Go to Step 17

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If there was a large amount of debris collected in the shop towel from the compressor hose assembly, replace the accumulator. Refer to Air Conditioning Accumulator Replacement .

Is the repair complete?

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Go to Step 17

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1. Install the suction and discharge lines. Refer to Suction Hose Replacement and Discharge Hose Replacement .
2. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
3. Leak test the refrigerant system. Refer to Leak Testing

Are the repairs complete?

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Go to Step 18

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Take readings of the low and high side pressures as well as the IP outlet air temperature after repairs are performed.

Compare the pressures and outlet temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test .

Are the readings within the specified ranges?

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Go to Step 19

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

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Symptoms - HVAC Systems - Automatic