Diagnostic Methods Overview

The Diagnostic Methods provide detailed instructions on how to access or perform routine diagnostic tasks. This information can be referenced for step-by-step instructions for routine procedures.

When performing powertrain diagnostics on On-Board Diagnostics II (OBD II) vehicles, the system may be checked by an off board tester referred to as a scan tool. The Diagnostic Methods contains instructions for performing diagnostics with the New Generation STAR (NGS) tester scan tool and the Generic Scan Tool (GST). A GST has a capability that is standard across the automotive industry in the United States. However, to perform manufacturer-specific functions, a string of characters must be entered manually. If NGS is used, those functions are selected from a menu. If using a GST to perform diagnostics, refer to the manufacturer's information for PID string characters.