GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2003 🢒 Envoy - 2WD 🢒 Brakes 🢒 Antilock Brake System 🢒 Diagnostic System Check - ABS

Circuit Description

The ABS Diagnostic System Check is an organized approach to identifying problems associated with the ABS. This must be the starting point for any ABS related concern and will direct you to the next logical step in diagnosing a malfunction. Most system malfunctions are linked to faulty wiring, connections and occasionally, to components. Understanding the ABS system and using the diagnostic tables correctly will reduce diagnostic time and prevent unnecessary parts replacement.

Test Description

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

  1. Lack of communication may be due to partial or total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.

    2.

  2. The presence of DTCs that begin with a "U" indicates that some other module is not communicating. The specified procedure will compile all of the available information before tests are performed.

Step

Action

Yes

No

1

Install a scan tool.

Does the scan tool power up?

Go to Step 2

Go to Scan Tool Does Not Power Up in Data Link Communications

2

  1. Turn the ignition ON.
  2. Use the scan tool in order to establish communication with the following modules:
    3. • 4WAL 3 Sensor
    • Powertrain
    • Instrument Panel Cluster
    • Body Control Module

Does the scan tool communicate with all of the control modules listed above?

Go to Step 3

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

3

Use the scan tool in order to display DTCs for the following control modules:

    • 4WAL 3 Sensor
    • Powertrain
    • Instrument Panel Cluster
    • Body Control Module

Does the scan tool display any DTCs for the control modules listed above?

Go to Step 4

Go to Symptoms - Antilock Brake System

4

Does the scan tool display any DTCs that begin with a "U", DTC C0290, C0292-C0297?

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

Go to Step 5

5

Does the scan tool display DTC P0500, P0502, P0503, P0562, P0563, P0601-P0607, P1381, P1621, P1627 or P1683?

Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 4.2L or Diagnostic Trouble Code (DTC) List in Engine Controls 4.8L, 5.3L, and 6.0L

Go to Step 6

6

Does the scan tool display DTC B1372?

Go to Diagnostic Trouble Code (DTC) List in Instrument Panel, Gages, and Console

Go to Diagnostic Trouble Code (DTC) List