GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Has the diagnostic system check been performed?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Connect the Scan Tool .
  2. Inspect for any DTCs.

Are any HVAC DTCs present?

--

Go to DTC Table

Go to Step 3

3

Using the Scan Tool view A/C system pressures.

Is the A/C system pressure normal?

--

Go to Step 4

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

4

  1. Ensure the ambient temperature is 4°C (39°F) or higher.
  2. Ensure the engine is warm and idling.
  3. Set the control assembly to 29°C (85°F).
  4. Set the passenger temperature to the coldest setting.
  5. Compare the outlet temperature between the left and the right center outlets.

Is the right center outlet air temperature cooler than the left outlet?

--

Go to Step 5

Go to Step 6

5

  1. Set the control assembly to 18°C (65°F).
  2. Set the passenger temperature to the warmest setting.
  3. Compare the outlet temperature between the left and the right center outlets.

Is the right center outlet air temperature warmer than the left outlet?

--

System OK

Go to Step 6

6

Inspect the door/actuator for the proper mounting or movement.

Do the actuators operate correctly?

--

Go to Step 8

Go to Step 7

7

Repair the actuator or door so that it operates correctly?

Is the repair complete?

--

Go to Step 9

--

8

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

Does the system operate correctly?

--

Go to Step 9

--

9

Confirm proper operation of the system.

Does the system operate correctly?

--

System OK

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