For 1990-2009 cars

### Test Description

The number below refers to the step number on the diagnostic table.

1. This step tests the HVAC control assemblies ability to reverse the polarity of the door control A and door control B circuits. The test lamp should illuminate.

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

1. Turn the ignition ON, with the engine OFF.
2. Place the blower motor switch to the low speed position.
3. Place the mode switch in the vent position.
4. Lower the glove box off its upper attachments.
5. Place the recirculation switch in the ON position.
6. Observe the recirculation door.
7. Place the recirculation switch in the OFF position.

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

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3 |

1. Turn the ignition OFF.
2. Disconnect the recirculation actuator.
3. Turn the ignition ON, with the engine OFF.
4. Connect a test lamp between the recirculation door control A circuit and the recirculation door control B circuit of the recirculation actuator.
5. Place the recirculation switch in the ON position.

Does the test lamp illuminate?

Go to Step 5

Go to Step 4

4 | Connect a test lamp between the recirculation door control B circuit of the recirculation actuator and a good ground. Does the test lamp illuminate? | Go to Step 7 | Go to Step 8
5 | Place the recirculation switch in the OFF position. Does the test light illuminate? | Go to Step 6 | Go to Step 10
6 | Inspect the recirculation door and the recirculation actuator for the following conditions:

• | A misaligned recirculation actuator--Refer to Recirculation Actuator Replacement .

• | Broken or binding linkages or recirculation door

• | An obstruction that prevents the recirculation actuator from operating within the full range of motion

• | Missing seals to the recirculation door

• | Misaligned seals to the recirculation door

Did you find and correct the condition?

Go to Step 13

Go to Step 9

7 | Test the recirculation door control A circuit of the HVAC control assembly for a short to ground, short to voltage, an open and for a high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 10
8 | Test the recirculation door control B circuit of the HVAC control assembly for a short to ground, short to voltage, an open and for a high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 10
9 | Inspect for poor connections at the harness connector of the recirculation actuator. 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 11
10 | Inspect for poor connections at the harness connector of the HVAC control assembly. 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
11 | Replace the recirculation actuator. Refer to Recirculation Actuator Replacement . Did you complete the replacement? | Go to Step 13 | --
12 | Replace the HVAC control assembly. Refer to Heater and Air Conditioning Control Replacement . 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