The present invention relates to a system and method for diagnosing and isolating problems and for monitoring operting conditions on an automobile. The system includes a hand held unit and a master station which can operate alone or in unison to accomplish functions such as logging and displaying data...http://www.google.de/patents/US6181992?utm_source=gb-gplus-sharePatent US6181992 - Automotive diagnostic service tool with hand held tool and master controller
