GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2004 🢒 Matiz 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 Cooling Insufficient - Air Conditioning (A/C) Inoperative

Step

Action

Values

Yes

No

1

Can you verify the customer complaint?

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Go to Step 2

System OK

2
  1. Inspect the fuses Ef14, Ef19, and Ef12.
  2. Inspect the blower fan operation.
  3. Inspect the engine cooling fan operation.
  4. Inspect the A/C compressor belt.
  5. Inspect the A/C condenser for restricted air flow.
  6. Inspect the slippage of the compressor clutch.
  7. Repair or replace any components as needed.
  8. Inspect the A/C system operation.

Is the A/C system operation normal?

--

System OK

Step 3

3
  1. Turn the ignition switch OFF.
  2. Connect the high and the low pressure gages.

Are both pressures within the value specified?

Low Side Pressure: 200 kPa (29 psi)

High Side Pressure: 1,500 kPa (217.5 psi)

Go to Step 8

Go to Step 6

4

Are both pressures above the specified value?

Low Side Pressure: 200 kPa (29 psi)

High Side Pressure: 1,500 kPa (217.5 psi)

Go to Step 5

--

5

Are both pressures within the specified value?

Low Side Pressure: 200 kPa (29 psi)

High Side Pressure: 1,500 kPa (217.5 psi)

Go to Step 8

--

6

Are both pressures below the specified value?

Low Side Pressure: 200 kPa (29 psi)

High Side Pressure: 1,500 kPa (217.5 psi)

Go to Step 7

Go to Step 4

7
  1. Add the refrigerant R-134a.
  2. Inspect the A/C system for leaks.
  3. Repair any refrigerant leaks as needed.
  4. Recover, evacuate, and recharge the A/C system.

Are both pressures within the specified value?

Low Side Pressure: 200 kPa (29 psi)

High Side Pressure: 1,500 kPa (217.5 psi)

Go to Step 8

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8
  1. Start the engine and allow it to run at idle.
  2. Set the A/C controls to the following positions:
    3. • The A/C switch to the ON position
    • The fresh air control switch to fresh air
    • The blower motor to 4
    • The temperature to full cold

Does the A/C compressor clutch engage?

--

Go to Step 9

Go to Step 11

9
  1. Inspect for a knocking noise from the A/C compressor.
  2. Cycle the A/C compressor ON and OFF in order to verify the source of the noise.

Do you hear a loud knocking noise?

--

Go to Step 10

Go to Step 14

10
  1. Recover the A/C system refrigerant.
  2. Replace the A/C compressor.
  3. Evacuate and recharge the A/C system.
  4. Inspect the A/C system for leaks.

Is the repair complete?

--

Go to Step 14

--

11
  1. Turn the ignition switch OFF.
  2. Disconnect the A/C compressor clutch coil connector.
  3. Connect a jumper wire from ground to one A/C compressor clutch coil terminal.
  4. Connect a fused jumper wire from the positive battery terminal to the other A/C compressor clutch coil terminal.

Does the A/C clutch engage?

--

Go to Step 12

Go to  Step 13

12

Repair the electrical circuit to the A/C compressor clutch coil.

Does the A/C clutch engage?

--

Go to Step 20

Go to Step 13

13

Replace the A/C compressor clutch coil.

Does the A/C clutch engage?

--

Go to Step 9

Go to Step 10

14

Important: Perform this test under garage conditions, 21-32°C (70-90°F), and no sun load. Follow this test carefully for accurate results.

  1. Close all of the windows and the doors of the vehicle.
  2. Set the A/C controls to the following positions:
    3. • The A/C switch to the ON position
    • The fresh air control switch to fresh air
    •  The blower motor to 4
    • The temperature to full cold
  3. Start the engine and follow it to run at idle for 5 minutes.
  4. Feel the evaporator inlet and outlet pipes.

Is there a noticeable difference in the temperature of the evaporator inlet and outlet pipes?

--

Go to Step 16

Go to Step 15

15
  1. Recover the A/C system refrigerant.
  2. Replace the expansion valve as needed.
  3. Evacuate and recharge the A/C system.
  4. Inspect the A/C system for leaks.
  5. Note the discharge air temperature with the A/C ON.

Is the discharge temperature normal?

--

Go to Step 16

Go to Step 18

16

Feel the liquid pipe between the condenser and the expansion valve.

Is the pipe cold?

--

Go to Step 19

Go to Step 17

17
  1. Remove the restriction of the high pressure side.
  2. Inspect the A/C system for leaks.

Is the repair complete?

--

System OK

--

18
  1. Recover the A/C system refrigerant.
  2. Evacuate and recharge the A/C system.
  3. Inspect the A/C system for leaks.

Is the repair complete?

--

System OK

--

19
  1. Run the engine at 3,000 RPM.
  2. Close all of the windows and doors of the vehicle.
  3. Set the A/C controls to the following positions:
    4. • The A/C switch to the ON position
    •  The fresh air control switch to fresh air
    • The blower motor to 4
    • The temperature to full cold
  4. Turn the A/C switch ON and OFF every 20 seconds for 3 minutes.

Are the A/C compressor high and the low side pressures within the specified value of each other?

Low Side Pressure: 200 kPa (29 psi)

High Side Pressure: 1,500 kPa (217.5 psi)

System OK

Go to Step 22

20
  1. Turn the ignition switch OFF.
  2. Turn the A/C switch to the OFF position.
  3. Attempt to turn the clutch driver, not the pulley.

Can you turn the clutch driver freely by hand?

--

Go to Step 23

Go to Step 21

21
  1. Recover the A/C system refrigerant.
  2. Replace the A/C compressor.
  3. Evacuate and recharge the A/C system.

Is the repair complete?

--

System OK

--

22

Add the refrigerant R-134a.

Does the cooling performance improve?

--

System OK

Go to Step 23

23
  1. Recover the A/C system refrigerant.
  2. Replace the compressor.
  3. Evacuate and recharge the A/C system.
  4. Inspect the A/C system for leaks.

Is the repair complete?

--

System OK

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