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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2004 🢒 Malibu 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Air Delivery Improper

Diagnostic Aids
    • The condition may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • 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

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step drives the actuator in both directions. If the actuator door is already in the position you are attempting to drive it to, reverse the polarity to drive the actuator in opposite direction.

    2.

  2. This step replaces the mode actuator and performs recalibration of the mode actuator upon the replacement of the fuse stated in the mode actuator replacement.

Step

Action

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: Air does not flow correctly from the air distribution outlets.

1

Did you perform the Diagnostic System Check-Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Turn ON the ignition, with the engine OFF.
  2. Turn OFF the HVAC controls.

Is the blower motor OFF?

Go to Step 3

Go to Blower Motor Always On

3

Place the blower motor switch in each speed position.

Does the blower motor operate in each speed position?

Go to Step 4

Go to Blower Motor Inoperative

4

Does the blower motor operate at the desired speeds?

Go to Step 5

Go to Blower Motor Malfunction

5

Place the mode switch in each mode position.

Does the air flow from the correct air distribution outlets in each selected mode position?

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

Go to Step 6

6

Test the mode door control A circuit and the mode door control B circuit for the following:

    •  An open
    •  A high resistance
    • A short to ground
    • A short to voltage

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 7

7

  1. Turn OFF the ignition.
  2. Disconnect the HVAC Control Module.
  3. Connect a 10-amp fused jumper wire between the actuator door control A circuit of the mode actuator and battery positive voltage.
  4. Connect a 10-amp fused jumper wire between the actuator door control B circuit of the mode actuator and a good ground.
  5. Reverse the polarity between the Mode actuator control A and B circuits.

Does the actuator shaft rotate in both directions?

Go to Step 8

Go to Step 9

8

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 13

Go to Step 12

9

Inspect the mode door and actuator for the following conditions:

    • A misaligned mode actuator. Refer to Mode Actuator Replacement .
    • Broken or binding linkages or actuator door
    • An obstruction that prevents the actuator door from operating within its full range of motion
    • Missing seals to the actuator door
    • Misaligned seals to the actuator door

Did you find and correct the condition?

Go to Step 13

Go to Step 10

10

Inspect for poor connections at the harness connector of the mode 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 13

Go to Step 11

11

Important: Perform the recalibration procedure for the mode actuator after replacement.

Replace the mode actuator. Refer to Mode Actuator Replacement .

Did you complete the replacement?

Go to Step 13

--

12

Important: Perform the recalibration procedure for the HVAC control module.

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

Did you complete the replacement?

Go to Step 13

--

13

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3