GM Service Manual Online
For 1990-2009 cars only

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle .

Circuit/System Description

The secondary information centre (SIC) LCD display test is performed using a scan tool. It goes through a series of tests directly controlling all segments of the LCD display to verify correct operation.

Diagnostic Aids

    • This diagnostic is for the Type A and B infotainment systems secondary information centre (SIC) LCD display. .
    • Before diagnosis of the SIC LCD Display feature, make sure the primary controls of the associated components are functioning properly.

Reference Information

Scan Tool Reference

Control Module References

Component Testing

Important: It is recommended that component testing is performed before circuit testing when diagnosing infotainment unit functions.

  1. Connect a scan tool to the DLC and select Infotainment System / Audio System / Miscellaneous Tests / Priority Key Selection .
  2. Switch the infotainment unit on.
  3. The scan tool will display the current serial data at the top of the screen, and the Key Priority Signal and associated key number at the bottom of the screen.
  4. Press the Priority 1 soft key on the scan tool and check the infotainment unit switched to the Priority Key 1 settings. Verify the scan tool screen displays the selection of Priority 1.
  5. Press the Priority 2 soft key on the scan tool and check the infotainment unit switches to the Priority Key 2 settings. Verify the scan tool screen displays the selection of Priority Key 2.
  6. Press the Quit soft key to exit the test.
  7. If the Priority Key Selection function does not operate correctly, replace the infotainment unit.

Repair Instructions

Perform the Diagnostic Repair Verification .

Radio Replacement Infotainment Unit Replacement