Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: The blower motor is inoperative in all speed positions.

Did you perform the Vehicle Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle Control Systems

1. Turn ON the ignition, with the engine OFF.
2. Place the blower motor switch in each speed position.

Does the blower motor operate in any of the speed positions?

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Go to Blower Motor Malfunction

Go to Step 3

1. Place the blower motor switch in the maximum speed position.
2. With the scan tool observe the Commanded Blower parameter in the HVAC Systems Automatic data list.

Does the scan tool indicate that the Commanded Blower parameter is near the specified value?

100%

Go to Step 4

Go to Step 10

1. Turn OFF the ignition.
2. Disconnect the blower motor connector.
3. Turn ON the ignition, with the engine OFF.
4. Connect a test lamp between the blower motor supply voltage circuit and the blower motor ground circuit.

Does the test lamp illuminate?

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Go to Step 9

Go to Step 5

Test the battery positive voltage circuit of the blower motor 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?

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Go to Step 13

Go to Step 6

Test the ground circuit of the blower motor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 13

Go to Step 7

1. Turn OFF the ignition.
2. Disconnect the blower motor connector.
3. Turn ON the ignition, with the engine OFF.
4. Connect a test lamp between the blower motor supply voltage circuit and the blower motor control circuit.
5. Adjust the blower controls from high speed to low speed.

Does the test lamp change intensity with the movement of the controls?

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Go to Step 9

Go to Step 8

Test the blower motor speed control circuit of the HVAC control module for an open, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 13

Go to Step 10

Inspect for poor connections at the harness connector of the blower motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 13

Go to Step 11

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 in Wiring Systems.

Did you find and correct the condition?

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Go to Step 13

Go to Step 12

Replace the blower motor. Refer to Blower Motor Replacement in Heating, Ventilation and Air Conditioning.

Did you complete the replacement?

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Go to Step 13

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Replace the HVAC control module. Refer to HVAC Control Module Replacement .

Did you complete the replacement?

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Go to Step 13

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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