GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: HVAC Schematics

DEFINITION: Air recirculation is inoperative or is always ON.

1

Did you perform the HVAC Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Automatic

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, perform the Recalibrate all Motors command in Instrument Panel Module Special Functions.
  4. With a scan tool, observe the current DTC list in Instrument Panel Module.

Does the scan tool display any DTCs?

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3

  1. Turn the ignition ON, with the engine OFF.
  2. Place the blower motor switch in the maximum speed position.
  3. Place the mode switch in the bi-level position.
  4. Alternately place the recirculation switch in the recirculation and outside air positions.

Does the recirculation door move from the recirculation position to the outside air position?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 4

4

  1. With a scan tool, observe the Air Inlet Dr Commanded parameter in the Instrument Panel Module data list.
  2. Alternately place the recirculation switch in the recirculation and outside air positions.

Does the scan tool indicate that the Air Inlet Dr Commanded parameter changes for each change in selected position?

Go to Step 6

Go to Step 5

5

  1. With a scan tool, command the recirculation door from OUTSIDE to RECIRC.
  2. Observe the Air Inlet Door Commanded parameter.

Does the scan tool indicate that the Air Inlet Commanded parameter changes?

Go to Step 12

Go to Step 10

6

Test the battery positive voltage circuit and the ground circuit of the recirculation actuator for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 7

7

Inspect the air distribution system for the following conditions:

    • A dirty HVAC air filter (if applicable)
    • An obstruction to the air flow
    • Air leaks
    • Misaligned air ducts

Did you find and correct the condition?

Go to Step 15

Go to Step 8

8

Inspect the recirculation door and the recirculation actuator for the following conditions.

    • A misaligned recirculation actuator. Refer to Recirculation Actuator Replacement .
    • Broken or binding linkages or recirculation door.
    • An obstruction that prevents the recirculation actuator from operating within it's full range of motion.
    • Missing seals to the recirculation door
    • Misaligned seals to the recirculation door

Did you find and correct the condition?

Go to Step 15

Go to Step 9

9

Inspect for poor connections at the harness connector of the recirculation actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 11

10

Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 13

11

Inspect for poor connections at the harness connector of the instrument panel integration module (IPM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 14

12

Important: Perform the recalibration procedure for the recirculation actuator.

Replace the recirculation actuator. Refer to Recirculation Actuator Replacement .

Did you complete the replacement?

Go to Step 15

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13

Replace the HVAC control module. Refer to HVAC Control Module Replacement

Did you complete the replacement?

Go to Step 15

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14

Important: Perform the recalibration procedure for the instrument panel integration module (IPM).

Replace the instrument panel integration module (IPM). Refer to Instrument Panel Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 15

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15

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3