GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2003 🢒 Montana - 4WD 🢒 Brakes 🢒 Antilock Brake System 🢒 ABS Indicator Always On

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.

Diagnostic Aids

The malfunction must be present during diagnosis in order to prevent unnecessary parts replacement. Always begin diagnosis with Diagnostic System Check - ABS .

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests if the IPC is able to turn OFF 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
  1. Turn OFF the ignition for 5 seconds.
  2. Turn ON the ignition while observing the ABS indicator.

Does the ABS indicator illuminate for 2 seconds and then turn OFF?

Go to Diagnostic Aids

Go to Step 3

3

  1. Install a scan tool.
  2. Select the Instrument Panel Cluster Special Functions menu on the scan tool.
  3. Command the IPC Lamps OFF.

Does the ABS indicator turn OFF?

Go to Step 5

Go to Step 4

4

Replace the instrument panel cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

Go to Step 6

--

5

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

Go to Step 6

--

6
  1. Turn OFF the ignition for 5 seconds.
  2. Turn ON the ignition while observing the ABS indicator.

Does the ABS indicator illuminate for 2 seconds and then turn OFF?

System OK

Go to Step 3