GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Engine Cooling Schematics DEFINITION: The auxiliary water pump will not turn OFF with the ignition in the ON position.

1

Did you perform the Engine Cooling Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Engine Cooling

2

  1. Turn OFF the ignition.
  2. Connect a 10amp fused jumper wire between pin 1 and pin 6 of the coolant fan test connector.
  3. Turn ON the ignition with the engine OFF.

Does the auxiliary water pump operate?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

  1. Turn OFF the ignition.
  2. Disconnect the K22 auxiliary water pump relay.
  3. Turn ON the ignition with the engine OFF.
  4. With a test lamp connected to a good ground, probe circuit X6 at the K22 relay connector.

Does the test lamp illuminate?

Go to Step 4

Go to Step 5

4

Connect a test lamp between circuit X6 and F5 of the K22 relay connector.

Does the test lamp illuminate?

Go to Step 7

Go to Step 6

5

Repair circuit X6, X2, X70, X68, X67, or X868 of the K22 relay for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 9

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6

Repair circuit F5 of the K22 relay for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 9

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7

Inspect for poor connections at the K22 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find the problem?

Go to Step 9

Go to Step 8

8

Replace the K22 auxiliary water pump relay.

Did you complete the repair?

Go to Step 9

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9

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2