GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: HVAC Schematics .

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 .

2

Did you read Air Delivery Description and Operation?

Go to Step 3

Go to Air Delivery Description and Operation Manual or Air Delivery Description and Operation Automatic.

3

  1. Start the engine.
  2. Place the mode switch in the OFF position.

Is the blower motor OFF?

Go to Step 4

Go to Blower Motor Always On .

4

Check for a jammed or broken actuator

Is a door broken or jammed

Go to HVAC Module Assembly Replacement .

Go to Step 5

5

  1. Place the mode switch in the vent position.
  2. Place the blower motor switch in each speed position.

Does the blower motor operate in any of the speed positions?

Go to Step 6

Go to Blower Motor Inoperative .

6

Does the blower motor operate at the desired speed?

Go to Testing for Intermittent Conditions and Poor Connections .

Go to Blower Motor Malfunction .