GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 Envoy - 2WD 🢒 Power and Signal Distribution 🢒 Wiring Systems and Power Management 🢒 Air Recirculation Malfunction

Diagnostic Aids
    • The condition may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections .
    • Inspect the air delivery system for the following conditions:
       - An obstruction to the airflow
       - Air leaks
       - Misaligned air ducts
       - Broken or binding linkages or doors
    • If the scan tool indicates that the Door Actual parameter is 5-10 counts from the Commanded Door parameter, then perform the recalibration procedure for the HVAC door actuators. Refer to Actuator Recalibration .

Step

Action

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?

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 Switch Parameter.
  3. Activate the recirculation switch.

Does the scan tool indicate that the Recirculate Switch Parameter changes state?

Go to Diagnostic Aids

Go to Step 3

3

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 5

Go to Step 4

4

Replace the HVAC control module. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 5

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5

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2