Schematic Reference: HVAC Schematics

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

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

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

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

Does the blower motor operate at the desired speeds?

Go to Step 5

Go to Blower Motor Malfunction

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

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

Go to Step 6

Go to Air Recirculation Malfunction

1. Install a scan tool.
2. Recalibrate the HVAC door actuators. Refer to Actuator Recalibration .
3. With a scan tool, observe the current DTC list in HVAC Systems Automatic.

Does the scan tool display any DTCs?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 7

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

Go to Step 8

1. With the scan tool, observe the Mode Door Position parameter in the HVAC Systems Automatic data list.
2. Place the mode switch in each mode position.

Does the scan tool display the correct state for each selected mode?

Go to Step 9

Go to Step 10

9

1. With the scan tool, observe the Mode Dr. Commanded parameter in the HVAC Systems Automatic data list.
2. Place the mode switch in each mode position.

Does the scan tool indicate that the Mode Dr. Commanded parameter is near the specified value in each mode position?

Go to Step 11

Go to Step 10

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 13

Go to Step 12

Inspect the air distribution system for the following conditions:

Did you find and correct the condition?

Go to Step 13

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

Did you complete the replacement?

Go to Step 13

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3