Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

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

1

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. Connect a test lamp between the blower motor supply voltage circuit and the blower motor control circuit.
4. Turn ON the ignition, with the engine OFF.
5. Place the blower motor switch in each speed position.

Does the test lamp illuminate in any speed position?

Go to Step 10

Go to Step 4

Test the blower motor supply voltage circuit 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 5

Test the blower motor control circuit for an open or high resistance between the blower motor and S255. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 6

1. Turn OFF the ignition.
2. Connect the blower motor.
3. Exchange the blower inhibit relay with a known good relay (the power window relay) from the instrument panel fuse block.
4. Turn ON the ignition, with the engine OFF.
5. Place the blower motor switch in each speed position.

Does the blower motor operate in any speed position?

Go to Step 11

Go to Step 7

1. Disconnect the blower inhibit relay.
2. Test the blower inhibit relay coil supply voltage circuit 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 8

Test the blower inhibit relay coil and switch ground circuits 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

Test the blower motor switch control circuit 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 12

Inspect for poor connections at 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

Inspect for poor connections at the blower inhibit relay. 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 blower switch. 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

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 inhibit relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 16

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Replace the blower switch. Refer to Heater and Air Conditioning Control Replacement .

Did you complete the replacement?

Go to Step 16

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2