GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Engine Cooling Schematics

DEFINITION: One or both engine cooling fan motors run continuously in high or low speed.

1

Did you perform the Engine Cooling Diagnostic System Check?

Go to Step 2

Go To Diagnostic System Check - Engine Cooling

2

Turn ON the ignition, with the engine OFF.

Are one or both cooling fans ON?

Go to Step 3

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

3

Are both cooling fans running continuously?

Go to Step 5

Go to Step 4

4

Remove the cooling fan relay.

Did the left cooling fan turn OFF?

Go to Step 6

Go to Step 7

5

Repair the short to voltage in the supply voltage circuit of the right cooling fan motor . Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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6

Repair the short to voltage in the low reference circuit of the cooling fan . Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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7

Repair the short to voltage in the supply voltage circuit of the left cooling fan motor . Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2