Fault Tracing Basics

Before Fault Tracing
Check the following items before attempting to diagnose fault codes:
- battery condition
- engine condition
- charging system
- auxiliary systems
- wire and cable connections
- ground point connections

Methods of Diagnosis
A system may be diagnosed with one or more diagnostic methods:
- Special test units
- Flash Codes
- ISAT scan tool

Many checks are carried out directly at the control unit connector. To make diagnostic "pin checks" easier, the preferred method is to use a breakout box.