GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Engine Cooling Schematics

Connector End View Reference: Cooling System Connector End Views

DEFINITION: The low coolant level display is always ON when the key is in the ON position.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Verify the coolant level is at the proper level in the surge tank.
  2. Turn ON the ignition, with the engine OFF.

Is the low coolant message displayed on the driver information center (DIC)?

Go to Step 3

Go to Testing for Electrical Intermittents in Wiring Systems

3

  1. Turn OFF the ignition.
  2. Disconnect the coolant level sensor.
  3. Inspect the ground circuit for an open or high resistance at the coolant level sensor connector.

Did you find and correct the condition?

Go to Step 10

Go to Step 4

4

  1. Turn ON the ignition, with the engine OFF.
  2. Inspect the control circuit at the coolant level sensor connector for a 12-volt signal.

Is 12 volts present on the control circuit?

Go to Step 6

Go to Step 5

5

Inspect the control circuit of the low coolant sensor for an open or short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

6

Inspect for poor connections at the coolant level sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 7

7

Replace the coolant level sensor. Refer to Radiator Surge Tank Replacement .

Did you complete the replacement?

Go to Step 10

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8

Inspect for poor connections at the Body Control Module (BCM). Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

9

Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3