Self-Diagnostic System: Notes
NOTE:
Diagnostic trouble code tests are written specifically for use with GM Tech I or Tech II scan tools. Generic scan tool can be used but may have limited functions. This article only covers the portion of those systems which relates to charging system diagnosis. For further information, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE or BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
Begin system diagnosis with diagnostic system check. Diagnostic system check will provide following information:
- Identification of control module(s) which command system.
- Ability of control module(s) to communicate through serial data circuit.
- Identification of any stored DTCs and their current status.