For 1990-2009 cars

Begin the diagnosis with the Diagnostic System Check - Defogger . The Diagnostic System Check will provide the following information:

• | The identification of the control modules which command the system

• | The ability of the control modules to communicate through the serial data circuit

• | The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.