Schematic Reference: HVAC Schematics

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

Did you perform the HVAC Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Manual

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 speed position?

Go to Blower Motor Malfunction

Go to Step 3

1. Turn OFF the ignition.
2. Disconnect the blower motor.
3. Turn ON the ignition, with the engine OFF.
4. Connect a test lamp between the blower motor supply voltage circuit and a good ground.
5. Place the blower motor switch in the minimum speed position.

Does the test lamp illuminate?

Go to Step 4

Go to Step 6

Connect a test lamp between the blower motor supply voltage circuit and the blower motor ground circuit.

Does the test lamp illuminate?

Go to Step 8

Go to Step 5

Test the ground circuit of the blower motor resistor 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 16

Go to Step 9

6

1. Turn OFF the ignition.
2. Disconnect the blower motor resistor assembly connector.
3. Turn ON the ignition, with the engine OFF.
4. Place the blower motor switch in the minimum speed position.
5. Connect a test lamp between the low blower motor control circuit of the blower motor resistor assembly and a good ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 7

7

1. Turn OFF the ignition.
2. Disconnect the HVAC control module.
3. Turn ON the ignition, with the engine OFF.
4. Connect a test lamp between the ignition 3 voltage circuit of the blower motor switch and a good ground.

Does the test lamp illuminate?

Go to Step 11

Go to Step 12

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?

Go to Step 16

Go to Step 13

Visually inspect the blower motor harness of the blower motor resistor assembly for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 10

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

Did you find and correct the condition?

Go to Step 16

Go to Step 14

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?

Go to Step 16

Go to Step 15

Repair the ignition 3 voltage circuit of the blower motor switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

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

Did you complete the replacement?

Go to Step 16

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

Did you complete the replacement?

Go to Step 16

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

Did you complete the replacement?

Go to Step 16

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3