DEFINITION: The low side pressure is lower than normal and the high side pressure is higher 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

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

Feel the liquid line at the front of dash.

Is the liquid line cold at the front of dash?

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Go to Step 3

Go to Step 8

Feel along the surface of the liquid line between the condenser and the front of dash.

Did you detect an abrupt drop in temperature along the surface?

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Go to Step 5

Go to Step 4

Feel along the surfaces of the following low side components:

Did you feel an abrupt temperature change along the surfaces of any of the listed components?

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Go to Step 5

Go to Step 6

1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
2. Remove the restriction from the component, or replace the component which produced an abrupt temperature drop.
3. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .

Is the repair complete?

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Go to Step 13

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The system may be low charged.

1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
2. Record the weight of the recovered refrigerant.

Is the weight of the recovered refrigerant charge less than the specified value?

Standard AC 0.625 kg (1.38 lbs)

Go to Step 7

Go to Step 10

The expansion device may be restricted or failed.

1. Remove the expansion device. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement .
2. Check the expansion device for a large amount of residue at the inlet.

Did you notice a residue at the inlet to the expansion device?

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Go to Step 8

Go to Step 11

The desiccant bag in the receiver portion of the condenser may have failed.

1. Remove the desiccant bag from the condenser. Refer to Air Conditioning Refrigerant Desiccant Replacement .
2. Check to see if the bag was broken.

Was the bag broken or leaking?

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Go to Step 9

Go to Step 12

1. Flush the A/C system. Refer to Flushing .
2. Replace the condenser. Refer to Air Conditioning Condenser Replacement .
3. Replace the A/C system. Refer to Refrigerant Recovery and Recharging .

Is the repair complete?

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Go to Step 13

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1. Test the system for any leakage. Refer to Leak Testing .
2. Repair any leaks found.
3. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .

Is the repair complete?

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Go to Step 13

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1. Replace the expansion device.
2. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .

Is the repair complete?

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Go to Step 13

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1. Replace the desiccant bag with a new unit.
2. Replace the expansion device.
3. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .

Is the repair 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 pressure and the panel outlet temperature to those listed in the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test .

Are the readings within the specified ranges listed in the A/C Performance Table?

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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 - Automatic