For 1990-2009 cars

#### A/C System Pressure -- Zone Classification

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Were you sent here from the Cooling Insufficient, A/C System diagnostic table? | -- | Go to Step 2 | Go to Cooling Insufficient - Air Conditioning (A/C) System
2 | After performing the A/C System Performance Test, did both the high and low side pressures fall within zone B on the A/C Pressure-Zone Classification Chart but after continued operation of the A/C system, did the low and high side pressures equalize or become static ? | -- | Go to Step 5 | Go to Step 3
3 | Refer to the pressures recorded. Check for the following conditions:

• | The low side pressure equal to or above the specified pressure range of the A/C Performance Table

• | The high side pressure is below the specified pressure range of the A/C Performance Table

• | The low side refrigerant line at the compressor feels cool to warm

• | The high side refrigerant line at the compressor feels warm to hot

Do the listed conditions exist ?

--

Go to Step 6

Go to Step 4

4 | Check for the following conditions:

• | The low side pressure is above the specified pressure range of the A/C Performance Table

• | The high side pressure is below the specified pressure range of the A/C Performance Table

• | The low side refrigerant line at the compressor feels warm

• | The high side refrigerant line at the compressor feels warm to hot

Do the listed conditions exist ?

--

Go to Step 5

Go to Cooling Insufficient - Air Conditioning (A/C) System

5 | The A/C compressor is malfunctioning. Replace the compressor. Refer to Air Conditioning Compressor Replacement Also replace the accumulator. Refer to Air Conditioning Accumulator Replacement Is the repair complete ? | -- | Go to Step 7 | --
6 | The A/C system has a low refrigerant charge. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging Is the repair complete ? | -- | Go to Step 7 | --
7 | Take readings of the low and high side pressures as well as the dash outlet air temperature after repairs are performed. Compare the pressures and outlet temperature to those listed in the A/C Performance Chart. Cooling Insufficient - Air Conditioning (A/C) System

Are the readings within the specified ranges ?

--

Go to Step 8

Go to Cooling Insufficient - Air Conditioning (A/C) System

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