System and method for reprogramming vehicle computers

摘要

A system and method for reprogramming a non-volatile memory of one or more on-board vehicle computers through a serial communication link between an off-board controller and the on-board vehicle computer. An interface circuit is also provided on the vehicle in order to process the command signals from the portable controller which will enable the non-volatile memory to receive and store new computer program code. The method follows a predetermined transfer protocol which assists in preventing the existing computer program code stored in the non-volatile memory from being improperly erased or re-written. This transfer protocol includes the transmission of a command signal from the off-board controller which has a voltage level that exceeds the voltage level of any signal which may recognized on the serial communication link.