For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Instrument Cluster Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Instrument Cluster
2 |

1. Turn the ignition switch to the ON position.
2. With a scan tool command the instrument cluster indicators ON.

Does the low coolant indicator lamp turn ON and OFF when commanded?

Go to Step 3

Go to Step 4

3 |

1. Disconnect the low coolant switch connector.
2. Connect a 3 Amp fused jumper wire between the signal circuit and the ground circuit of the low coolant switch connector.
3. With the scan tool, observe the LOW COOLANT LEVEL parameter in the BCM DATA list.

Does the LOW COOLANT LEVEL parameter display ON?

Go to Step 5

Go to Step 6

4 | Replace the instrument cluster (IPC). Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console. Did you complete the repair? | Go to Step 11 | --
5 | Inspect for poor connections at the harness connector of the low coolant switch. 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 11 | Go to Step 7
6 | Test the ground circuit of the low coolant switch for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 8
7 | Replace the low coolant switch. Did you complete the replacement? | Go to Step 11 | --
8 | Test the signal circuit of the low coolant switch for the following conditions:

• | An open

• | A short to voltage

• | A high resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 9

9 | Inspect for poor connections at the harness connector of the body control module (BCM). 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 11 | Go to Step 10
10 |

1. Replace the BCM. Refer to Body Control Module Replacement in Body Control System.
2. Perform the setup procedure for the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration .

Did you complete the replacement?

Go to Step 11

--

11 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2