GM Service Manual Online
For 1990-2009 cars only

Step

Action

Normal Result(s)

Abnormal Result(s)*

1

With scan tool connected make contact with any of the modules applicable to the vehicle

Scan Tools main menu.

    • Blank Screen
    • No power to the scan tool

Refer to Scan Tool Inoperative

2

  1. Select Body Diagnostics from the scan tools menu.
  2. Select any Class 2 Module Data Line information (all except SIR).
  3. Access main screen on the scan tool.

System Main screen appears

Scan tool will not communicate with the module(s)

Refer to Scan Tool Does Not Communicate with Class 2 Data Line

3

  1. Select Body Diagnostics from the scan tools menu.
  2. Select SIR UART Data Line information.
  3. Access main screen on the scan tool.

System Main screen appears

Scan tool will not communicate with the module(s)

Refer to Scan Tool Does Not Communicate with UART Data Line

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.