Initial Inspection and Diagnostic Overview

Diagnostic Starting Point - Heating, Ventilation and Air Conditioning

Begin the system diagnosis with Diagnostic System Check - Vehicle. 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.

Refer to Diagnostic System Check - Vehicle. Diagnostic System Check - Vehicle