Initial Inspection and Diagnostic Overview

Diagnostic Starting Point - Data Communications
Begin the system diagnosis with [Diagnostic System Check - Vehicle Diagnostic Information]. The Diagnostic System Check - Vehicle will provide the following information:
^ The identification of the control modules which are not communicating.
^ The identification of any stored diagnostic trouble codes (DTCs) and their status.

The use of the Diagnostic System Check - Vehicle will identify the correct procedures to begin vehicle diagnosis. These must be performed before system DTC or symptom diagnosis.