Diagnostic Methods: Overview

The Diagnostic Methods article provides information on routine diagnostic tasks.

When following powertrain diagnostics on OBD II vehicles, the system may be checked by an off-board tester referred to as a scan tool. This article contains information for performing diagnostics with a scan tool. A scan tool has certain generic capabilities that are standard across the automotive industry in the United States. All functions are selected from a menu. Refer to the instruction manual provided by the tool manufacturer.