GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Blazer - 4WD - RHD 🢒 Restraints 🢒 Seat Belts 🢒 Diagnostic System Check - Instrument Cluster

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

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

    2.

  2. There may be DTC's stored in other class 2 modules related to the instrument cluster.

    3.

  3. The presence of DTCs which begin with U indicate some other module is not communicating. The specified procedure will compile all 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 ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the following control modules (if using a Tech 2, obtain this information using the class 2 Message Monitor feature.):
    3. • Automatic Transfer Case (ATC)
    • Instrument Panel Cluster
    • Body Control Module
    • Vehicle Control Module (VCM)
    • Electronic Brake Control Module (EBCM) (4WAL 3 sensor)
    • Inflatable Restraint Sensing and Diagnostic Module (SDM)

Does the scan tool communicate with 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

Select the display DTCs function on the scan tool for the following control modules:

    • Automatic Transfer Case (ATC)
    • Instrument Panel Cluster
    • Body Control Module
    • Vehicle Control Module (VCM)
    • Electronic Brake Control Module (EBCM) (4WAL 3 sensor)
    • Inflatable Restraint Sensing and Diagnostic Module (SDM)

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

Go to Step 4

Go to Symptoms - Instrument Cluster

4

Does the scan tool display any DTCs which begin with a U?

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 B1397, B1398, or B1480?

Go to Diagnostic Trouble Code (DTC) List/Type in Body Control System

Go to Diagnostic Trouble Code (DTC) List/Type