GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Check for a faulty low coolant sensor.

Is the sensor faulty?

--

Go to Step 2

Go to Step 3

2

Replace the sensor. Refer to Engine Coolant Level Indicator Module in Electrical.

Does the low coolant lamp continue to stay on?

--

Go to Step 3

System OK

3

Check for a faulty circuit.

Is the circuit faulty?

--

Go to Step 4

Go to Step5

4

Repair the circuit. Refer to Engine Coolant Level Indicator Module in Electrical.

Does the lamp stay on?

--

--

System OK

5

Check for a faulty engine coolant thermostat stuck closed.

Is the thermostat stuck closed?

--

Go to Step 6

--

6

Replace the engine coolant thermostat.

--

--

System OK