A computer-implemented method includes receiving a notification at a network server and directing the notification to a particular address of a plurality of addresses that are associated with a customer premises. The AD converting means has a first conversion mode in which the digital conversion is carried out with high conversion precision, and a second conversion mode in which the digital conversion is carried out with conversion precision lower than the first conversion mode. Thus, the characteristics of a gate insulating film formed on the walls of trenches are improved. After the message passes through the server, an application running on a device remote from the vehicle receives the request message and accepts user input that permits the remote device to transmit its current location to the vehicle-coupled device in a confirmation message according to the session identifier.