For 1990-2009 cars

### Circuit Description

The instrument cluster controls the operation of the ABS indicator. The electronic brake control module (EBCM) reports the desired status of the ABS indicator via serial data messages.

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. Use the scan tool to check the normal state of the ABS indicator control circuit.

2. Ensures that the instrument panel cluster (IPC) can operate the ABS indicator.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views or Instrument Panel, Gages, and Console Connector End Views in Instrument Panel, Gages, and Console
1 | Did you perform the ABS Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - ABS
2 | Inspect the EBCM ground, making sure the ground is clean and torqued to the proper specification. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 3
3 |

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With a scan tool, observe the ABS Warning Lamp parameter in the ABS data list.

Does the scan tool display Off?

Go to Step 4

Go to Step 5

4 |

1. Turn OFF the ignition.
2. Turn ON the ignition, with the engine OFF.
3. Observe the ABS indicator on the instrument panel cluster (IPC) during the displays test.

Does the ABS indicator illuminate during the displays test and then turn OFF?

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

Go to Step 6

5 | Inspect for poor connections at the harness connector of the EBCM. 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 9 | Go to Step 7
6 | Inspect for poor connections at the harness connector of the IPC. 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 9 | Go to Step 8
7 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the repair? | Go to Step 9 | --
8 | Replace the instrument panel cluster (IPC). Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console. Did you complete the repair? | Go to Step 9 | --
9 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2