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Test Description

WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

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

  1. 13:  The test lamp should illuminate while trying to command the appropriate mode door in both directions.
  2. 15:  Two ignition 3 voltage circuits supply the HVAC control module. Test the ignition 3 voltage circuit that does not supply the blower motor switch.
  3. 18:  Check the connection by removing and securely reinstalling before replacement of the HVAC control is considered.
Air Delivery Improper

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
2
  1. Turn ON the ignition, with the engine OFF.
  2. Place the blower motor switch in the OFF position.
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 any speed position?		 Go to Step 4  Go to Blower Motor Inoperative 
4 Does the blower motor operate in each speed position? Go to Step 5  Go to Blower Motor Malfunction 
5 Are all of the HVAC control module controls except for the blower motor inoperative? Go to Step 15  Go to Step 6 
6
  1. Place the blower motor switch in the maximum speed position.
  2. Place the mode switch in the vent position.
  3. Place the recirculation switch in the ON position.
  4. Observe the recirculation door.
  5. Place the outside air switch in the ON position.
Does the recirculation door move from the recirculation to the outside air position?		 Go to Step 7  Go to Air Recirculation Malfunction 
7
  1. Place the blower motor switch in the maximum speed position.
  2. Place the mode switch in each mode position.
Does air flow sufficiently from the proper air distribution outlets for each selected mode position?		 Go to Testing for Intermittent Conditions and Poor Connections Go to Step 8 
8 Inspect the air delivery system for the following conditions:
  • A dirty HVAC air filter, if applicable
  • An obstruction to the airflow
  • Air leaks
  • Misaligned air ducts

Did you find and correct the condition?		 Go to Step 21  Go to Step 9 
9 Inspect the appropriate mode door and the mode actuator for the following conditions:
Did you find and correct the condition?		 Go to Step 21  Go to Step 10 
10 Test the position signal circuit of the appropriate mode actuator for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 11 
11 Test the low reference circuit of the appropriate mode actuator for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 12 
12 Test the 5-volt reference circuit of the appropriate mode actuator for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 13 
13 
  1. Turn OFF the ignition.
  2. Reconnect the appropriate mode actuator.
  3. Turn ON the ignition with the engine OFF.
  4. Connect a test lamp between mode door control A and mode door control B circuits of the appropriate mode actuator connector.
  5. Place the mode switch in the Defrost position.
  6. Place the mode switch in the Panel position.
Does the test lamp illuminate in both positions?		 Go to Step 17  Go to Step 14 
14 Test the mode door control A and mode door control B circuits of the appropriate mode actuator for an open, a high resistance, a short to ground, or a short to voltage. Refer to Circuit Testing and to Wiring Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 18 
15  Test the ignition 3 voltage circuit of the HVAC control module for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 16 
16 Test the ground circuit of the HVAC control module for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 18 
17 Inspect for bad connections at the harness connector of the appropriate mode actuator. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 19 
18  Inspect for bad connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs .
Did you find and correct the condition?		 Go to Step 21  Go to Step 20 
19 Replace the appropriate mode actuator. Refer to Panel Actuator Replacement  or Defroster Actuator Replacement  or Floor Actuator Replacement .
Did you complete the replacement?		 Go to Step 21  -
20 Replace the HVAC control module. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?		 Go to Step 21  -
21 Operate the system in order to verify the repair.
Did you correct the condition?		 System OK Go to Step 8 
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