GM Service Manual Online
For 1990-2009 cars only

Step

Action

Values

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: Air recirculation is inoperative or always on.

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Recalibrate the motors. Refer to Actuator Recalibration .
  4. With a scan tool, observe the current DTC list in Instrument Panel Module.

Does the scan tool display any DTCs?

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Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

Go to Step 3

3

  1. Place the blower motor switch in the maximum speed position.
  2. Place the mode switch in the bi-level position.
  3. Alternately, place the recirculation switch in the recirculation and outside air positions.

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

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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 value of the Air Inlet Dr. Commanded parameter changes from the minimum specified value to the maximum specified value?

0-230 counts

Go to Step 6

Go to Step 5

5

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

Did you find and correct the condition?

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Go to Step 8

Go to Step 7

6

Inspect and the air distribution system for the following conditions:

  1. A restricted passenger compartment air filter.
  2. An obstruction restricting air flow.
  3. Air leaks.
  4. Misaligned ducts.

Did you find and correct the condition?

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Go to Step 8

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7

Replace the IPM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

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Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

 

System OK

Go to Step 3