ABS Indicator Always On. Chevrolet Joy 2008

For 1990-2009 cars

### Circuit Description

Battery voltage is supplied to the antilock brake system (ABS) warning lamp with the ignition switch in the ON or START position. The warning lamp should be activated only by the ABS control module internally supplying ground to terminal 10.

This procedure checks for a short to ground in the wiring or a defective electronic brake control module (EBCM).

### Conditions for Setting the DTC

• | There is a short to ground in the circuit between the cluster terminal B1 and the EBCM terminal 10.

• | The EBCM is faulty.

### Test Description

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

1. This step determines whether the EBCM is faulty.

2. This begins a search for a short to ground in the circuit between the ABS indicator lamp and the EBCM.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Inspect the electronic brake control module (EBCM) connector. Did you find and correct the condition? | Go to Step 8 | Go to Step 3

3

1. Disconnect the EBCM connector.
2. Turn the ignition switch to ON.
3. Use an insulated tool to push the shorting bar in the connector away from terminal 10.

Does the antilock brake system (ABS) indicator lamp go out?

Go to Step 4

Go to Step 5

4 | Replace the EBCM. Refer to Brake Pressure Modulator Valve Assembly Replacement . Did you complete the replacement? | Go to Step 8 | --

5

1. Turn the ignition switch to OFF.
2. Connect the EBCM connector.
3. Disconnect connector C103.
4. Turn the ignition switch to ON.

Does the ABS indicator lamp illuminate?

Go to Step 7

Go to Step 6

6 | Repair the short to ground in circuit between connector C103 and the EBCM connector. Did you complete the repair? | Go to Step 8 | --
7 | Repair the short to ground in circuit between the instrument panel cluster (IPC) connector B1 and connector C103. Did you complete the repair? | Go to Step 8 | --

8

1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK