Using Generic Scan Tool
WARNING: This page is about a different car, the 2002 Mercedes-Benz G500. However, it is still accessible from the selected car via links, so may be relevant.
Turn ignition off. Connect generic scan tool to diagnostic connector located under left side of dashboard. See Fig 1 . Turn ignition on. Follow tool manufacturer's instructions for reading fault codes. If no fault codes are present, but vehicle is experiencing a problem, go to TROUBLE SHOOTING - NO CODES (ENGINE 113 - G500) article.