Patent ID: 8035494

Claim:
Data transfer system for programming motor vehicle control devices comprising: a immobilizer control device ( 5 ), located on a vehicle to control the immobilization of the vehicle, which is adapted to store data which is to be protected against unauthorized access; a motor vehicle service tool ( 9 ); and, a vehicle manufacturer server ( 12 ), which is adapted to receive data which is to be protected against unauthorized access and is to be transferred to the immobilizer control device ( 5 ); wherein the immobilizer control device ( 5 ) and the motor vehicle service tool ( 9 ) are adapted to be connected to one another via a first data transfer device and for data stored in the immobilizer control device ( 5 ) to be transferred as first transfer data to the motor vehicle service tool ( 9 ), wherein the motor vehicle service tool ( 9 ) and the vehicle manufacturer server ( 12 ) are adapted to bring the motor vehicle service tool ( 9 ) from an area at the immobilizer control device ( 5 ) into a spatial area in which the motor vehicle service tool ( 9 ) can be connected to the vehicle manufacturer server ( 12 ) indirectly or directly via a second data transfer device ( 11 ), to connect the motor vehicle service tool ( 9 ) and the vehicle manufacturer server ( 12 ) indirectly or directly via the second data transfer device ( 11 ) and transfer at least a part of the first transfer data from the motor vehicle service tool ( 9 ) to the vehicle manufacturer server ( 12 ) as second transfer data; wherein the vehicle manufacturer server ( 12 ) is adapted to generate an authentication response value from the first transfer data or a part thereof by means of a generating function; wherein the motor vehicle service tool ( 9 ) and the vehicle manufacturer server ( 12 ) are adapted to transfer the authentication response value and data stored in the vehicle manufacturer server ( 12 ) as third transfer data to the motor vehicle service tool ( 9 ); wherein the immobilizer control device ( 5 ) and the motor vehicle service tool ( 9 ) are adapted to transfer the authentication response value and the other third transfer data or part thereof to the immobilizer control device ( 5 ) as fourth transfer data; wherein the immobilizer control device ( 5 ) is adapted to check the correctness of the authentication value by means of the first transfer data or parts thereof and to process the fourth transfer data further; and when the immobilizer control device determines the authentication value is correct, the motor vehicle service tool is then capable of gaining protected access to the immobilizer control device.