Patent 7100557 was granted and assigned to NISSAN MOTOR CO.,LTD. on September, 2006 by the United States Patent and Trademark Office.
An engine start control system of the present invention has a power supply controller which includes an ignition power supply relay activating an electric component of a vehicle and a central processing unit controlling the ignition power supply relay, a communication device communicating with a portable unit to authenticate a validity of the portable unit and performing engine start control. Further, the engine start control system has the a first drive line provided between the communication device and the ignition power supply relay and not routed through the central processing unit. By this structure, the system can obtain redundancy.