Did you perform the HVAC Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check

IMPORTANT: Outside air temperature must be above 16°C (60°F).

1. Start the engine.
2. Fully open all panel outlets.
3. Adjust temperature to COOL.
4. Select MAX A/C mode.
5. Set blower speed to maximum.
6. Ensure that the VENT mode indicator is not illuminated.

Does the A/C compressor operate?

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Go to Step 3

Go to HVAC Compressor Clutch Does Not Engage

Does the blower operate and provide sufficient airflow?

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Go to Step 4

Go to Blower Motor Does Not Operate Properly

Use the heater and A/C control to adjust the temperature from COOL to WARM.

Does the air mix actuator rotate with each command?

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Go to Step 5

Go to Step 6

Perform the refrigerant system performance test. Refer to System Performance Test .

Are low and high side pressures within specification?

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System OK

Go to VDOT Air Conditioning (A/C) System Diagnosis

1. Turn the ignition OFF.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, command the Temp. door position from Hot to Cold.

Does the air mix actuator rotate with each command?

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Go to Step 15

Go to Step 7

1. Turn the ignition OFF.
2. Disconnect the air mix actuator.
3. Turn ON the ignition, with the engine OFF.
4. Measure the voltage from the supply circuit of the air mix actuator to a good ground.

Does the voltage measure near the specified value?

12V

Go to Step 8

Go to Step 10

Measure the voltage from the supply circuit of the air mix actuator to the motor return circuit of the air mix actuator.

Does the voltage measure near the specified value?

12V

Go to Step 9

Go to Step 11

1. Measure the voltage from the motor drive circuit of the air mix actuator to the motor return circuit of the air mix actuator.
2. With a scan tool, command the Temp. door position from Hot to Cold.

Does the voltage change?

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Go to Step 13

Go to Step 12

1. Turn the ignition OFF.
2. Test the supply circuit of the air mix actuator for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

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Go to Step 18

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1. Turn the ignition OFF.
2. Test the motor return circuit of the air mix actuator for an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

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Go to Step 18

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1. Turn the ignition OFF.
2. Test the motor drive circuit of the air mix actuator for an open, a short to ground or a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

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Go to Step 18

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1. Turn the ignition OFF.
2. Inspect for poor connections at the harness connector of the air mix actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

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Go to Step 18

Go to Step 14

Inspect the air mix actuator and air mix doors for binding or mechanical failure.

Did you find and correct the condition?

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Go to Step 18

Go to Step 16

Inspect for poor connections at the harness connector of the heater and A/C control. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

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Go to Step 18

Go to Step 17

Replace the air mix actuator. Refer to Temperature Actuator Replacement .

Did you complete the replacement?

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Go to Step 18

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Replace the heater and A/C control. Refer to Control Assembly Replacement .

Did you complete the replacement?

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Go to Step 18

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Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2