Schematic Reference: HVAC Schematics

Did you review the Air Delivery Description and Operation and the Air Temperature Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - HVAC Systems - Manual

Operate the blower motor at each speed.

Does the blower motor operate at any speed?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

1. Disconnect the blower motor connector.
2. Connect a test lamp across the connector.
3. Turn the ignition switch ON.
4. Turn the blower switch to any position except OFF.

Does the test lamp illuminate?

Go to Step 12

Go to Step 4

1. Turn the blower switch OFF.
2. Test for battery voltage at the blower motor. Refer to Circuit Testing in Wiring Systems.

Is battery voltage present?

Go to Step 9

Go to Step 5

Test the blower motor supply voltage circuit 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 6

Test the blower relay switch supply voltage circuit 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 7

Test the blower relay coil supply voltage circuit 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 8

Test the blower relay coil ground circuit 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 13

Test the blower motor ground circuit for an open between the blower motor and S204. 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

Test the blower switch ground circuit 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 11

Test the blower switch for a high resistance or for an open in each speed position. Refer to Circuit Testing in Wiring Systems and Blower Switch Replacement .

Did you find and correct the condition?

Go to Step 16

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Inspect for a poor connection 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 14

Inspect for a poor connection at the harness connector of the blower motor 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 15

Replace the blower motor. Refer to Blower Motor and Fan Replacement .

Did you complete the replacement?

Go to Step 16

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Replace the blower motor relay. Refer to Blower Motor Relay 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 3