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 |

1. Start the engine.
2. Turn the A/C ON.
3. Feel the liquid line before the expansion (orifice) tube.

Is the liquid line cold before the orifice?

--

Go to Step 3

Go to Step 8

3 | 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.)

• | The compressor discharge hose

• | The condenser

• | The liquid line between the condenser and the orifice

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

--

Go to Step 7

Go to Step 4

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? | -- | Go to Step 11 | Go to Step 5
5 | Feel along the surfaces of the following low side components for a sudden change in temperature.

• | The liquid line between the orifice and the evaporator core

• | The vapor hose between the evaporator core and the accumulator

• | The accumulator

• | The compressor suction hose

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

--

Go to Step 7

Go to Step 6

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

• | The liquid line between the orifice and the evaporator core

• | The vapor hose between the evaporator core and the accumulator

• | The accumulator

• | The compressor suction hose

• | The compressor discharge hose

• | The condenser

• | The liquid line between the condenser and the orifice

Are the overall temperatures of the low and high side components close to the same (both only mildly warm) ?

--

Go to Step 12

Go to Step 8

7 |

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.

Is the repair complete?

--

Go to Step 15

--

8 |

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

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

0.57 kg (1.25 lb)

Go to Step 9

Go to Step 9

9 | Recharge the A/C system. Refer to Refrigerant Recovery and Recharging Does the cooling performance improve? | -- | Go to Step 15 | Go to Step 10
10 |

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

Is the repair complete ?

--

Go to Step 15

--

11 |

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

Is the repair complete?

--

Go to Step 15

--

12 |

1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging
2. Disconnect the compressor hose from the compressor. Refer to Compressor Hose Assembly Replacement
3. Inspect for the presence of debris on the compressor suction port screen.

Is there debris present on the compressor suction port screen?

--

Go to Step 13

Go to Step 14

13 |

1. Remove the debris from the suction port screen.
2. Inspect the orifice for damage. Refer to Expansion (Orifice) Tube Replacement
3. If the orifice does not show any signs of damage replace the accumulator. Refer to Air Conditioning Accumulator Replacement

Is the repair complete?

--

Go to Step 14

--

14 |

1. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging
2. Leak test the refrigerant system. Refer to Leak Testing

Are the repairs completed?

--

Go to Step 15

--

15 | 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. Are the readings within the specified ranges? | -- | Go to Step 16 | Go to Cooling Insufficient - Air Conditioning (A/C) System
16 | Operate the system in order to verify the repair. Did you correct the condition? | -- | Go to Step 17 | Go to Symptoms in HVAC System - Manual
17 | Disconnect the J 39500-B Is the operation complete? | -- | System OK | --