For 1990-2009 cars

## Air Recirculation Malfunction Oldsmobile Only

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. There are two ignition 3 voltage circuits at the HVAC control module. Test the circuit that is not the supply voltage circuit for the blower motor switch.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: HVAC Schematics DEFINITION: Air recirculation is inoperative or is always ON.
1 | Did you perform the HVAC Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - HVAC Systems - Manual
2 |

1. Start the engine.
2. Place the mode switch in the vent position.
3. Place the blower motor switch in the maximum speed position?
4. Place the outside air switch in the ON position.
5. Place the recirculation switch in the ON position.

Does the recirculation door operate properly?

Go to Step 3

Go to Step 4

3 | Place the mode switch in the defrost position. Does the recirculation door move to the outside air position? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 8
4 | Does the air temperature switch operate properly? | Go to Vacuum Control System Diagnostic | Go to Step 5
5 | Test the ignition 3 voltage circuit of the HVAC control assembly for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 6
6 | Test the battery positive voltage circuit of the HVAC control assembly for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 7
7 | Test the ground circuit of the HVAC control assembly for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 8
8 | Inspect for poor connections at the harness connector of the HVAC control assembly. Refer to Testing for Intermittent Conditions and Poor Connections and in Connector Repairs Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 9
9 | Replace the HVAC control assembly. Refer to Heater and Air Conditioning Control Replacement . Did you complete the replacement? | Go to Step 10 | --
10 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2