Schematic Reference: Engine Cooling Schematics

DEFINITION: The engine cooling fan motor does not operate.

Did you perform A Diagnostic System Check-Engine Cooling?

Go to Step 2

Go to Diagnostic System Check - Engine Cooling

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With a scan tool, command the cooling fan ON and OFF.

Does the engine cooling fan turn ON and OFF with each command?

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

Go to Step 3

1. Turn OFF the ignition.
2. Remove the cooling fan relay.
3. Turn the ignition ON, with the engine OFF.
4. Probe the battery positive voltage circuit of the cooling fan relay switch side with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 7

Connect a 20 A fused jumper wire between the battery positive voltage circuit of the cooling fan relay and the cooling fan motor supply voltage circuit of the cooling fan relay.

Does the cooling fan operate?

Go to Step 10

Go to Step 5

1. Turn OFF the ignition.
2. Disconnect the cooling fan connector.
3. Turn the ignition ON, with the engine OFF.
4. Probe the cooling fan motor supply voltage circuit at the harness connector with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 8

Probe the harness connector of the cooling fan motor with a test lamp connected between the cooling fan motor supply voltage circuit and the ground circuit of the cooling fan motor.

Does the test lamp illuminate?

Go to Step 11

Go to Step 9

Repair the battery positive circuit of the cooling fan relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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Repair the supply voltage circuit of the cooling fan motor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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Repair the ground circuit of the cooling fan motor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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Inspect for poor connections at the cooling fan 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 14

Go to Step 12

Inspect for poor connections at the harness connector of the cooling fan 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 14

Go to Step 13

Replace the cooling fan relay.

Did you complete the repair?

Go to Step 14

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Replace the cooling fan motor. Refer to Engine Cooling Fan Replacement .

Did you complete the repair?

Go to Step 14

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2