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 is 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

2

  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool observe the Recirculate Mode Parameter.
  3. Place the recirculation switch in the recirculate position.

Does the scan tool indicate that the recirculation switch changes state?

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Go to Step 3

Go to Step 11

3

  1. Turn OFF the ignition.
  2. Disconnect the recirculation actuator.
  3. Turn On the ignition, with the engine OFF.
  4. Probe the ignition 3 voltage circuit of the recirculation actuator with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 8

4

Test the low reference circuit of the recirculation actuator for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 5

5

  1. Measure the voltage from the door control circuit of the recirculation actuator to a good ground.
  2. Place the recirculation switch in the outside air position.

Does the voltage measure near the specified value?

0 V outside air

Go to Step 6

Go to Step 7

6

  1. Measure the voltage from the door control circuit of the recirculation actuator to a good ground.
  2. Place the recirculation switch in the recirc position.

Does the voltage measure near the specified value?

12 V recirc

Go to Step 9

Go to Step 7

7

Test the recirculation door control circuit of the recirculation actuator for an open, a high resistance, a short to ground, or a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 10

8

Repair the ignition 3 voltage circuit of the recirculation actuator. Refer to Wiring Repairs .

Did you complete the repair?

--

Go to Step 14

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9

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

    • A misaligned recirculation actuator
    • Broken or binding linkages
    • A broken or binding recirculation door
    • An obstruction that prevents the recirculation door from operating within its 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 14

Go to Step 10

10

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

Did you find and correct the condition?

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Go to Step 14

Go to Step 12

11

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 .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 13

12

Replace the recirculation actuator. Refer to Recirculation Actuator Replacement .

Did you complete the replacement?

--

Go to Step 14

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13

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

Did you complete the replacement?

--

Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3