GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Brakes 🢒 Air Antilock Brake System 🢒 Air ABS Indicator Inoperative

Circuit Description

The EBCM sends a central area network (CAN) serial data message to the serial data gateway (SDG) module. The SDG module converts the CAN message to a class 2 serial data message and sends the message to the instrument panel cluster (IPC). The IPC interprets the class 2 message from the SDG module and commands the ABS indicator ON or OFF.

Diagnostic Aids

Replace the Instrument Panel Cluster if the ABS indicator intermittently fails to operate during the bulb check.

Test Description

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

  1. This step tests if the IPC is able to illuminate the ABS indicator during the bulb check.

Step

Action

Yes

No

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?

Go to Diagnostic Aids

Go to Step 3

3

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

Did you complete the replacement?

Go to Step 4

--

4
  1. Turn OFF the ignition for 5 seconds.
  2. Turn ON the ignition while observing the ABS indicator.

Does the ABS indicator illuminate?

System OK

Go to Step 3