Abstract: A method for adjusting a clock on board a motor vehicle, the clock providing an actual time for functions of the vehicle, the vehicle connected via wireless communication to a data server, the method including: the server transmitting a sequence of consecutive actual-time values, separated from one another by a fixed time interval; the vehicle receiving the actual-time values shifted by an unknown and variable time of flight between transmission and reception; for each received actual-time value: calculating a difference between an actual-time value received at a given instant and an actual-time value received at a previous instant; calculating a discrepancy between the calculated difference and the fixed time interval; calculating a cumulative disparity, consisting in summing the discrepancy calculated for a time value received at one instant and a time value received at the previous instant; determining the actual time for adjusting the on-board clock according to the disparity.

Abstract: A method of unlocking the anti-starting system of a computer (ECM) controlling the operation of an engine of a motor vehicle, includes: each time the computer is powered up generating therewith a first random value and writing the value into a first zone of a volatile memory of the computer, downloading an unlocking program from a downloading tool to the volatile memory, the execution of which generates the calculation of a second value from the first random value and from a determined relation stored in the unlocking program, and writing the second value into a second zone of the volatile memory of the computer, reinitializing the software of the computer without erasing the first and second zones of the volatile memory of the computer, comparing the values stored in the first and second zones, unlocking the anti-starting system of the computer, if the comparison is successful.

Abstract: A method of unlocking the anti-starting system of a computer (ECM) controlling the operation of an engine of a motor vehicle, includes: each time the computer is powered up generating therewith a first random value and writing the value into a first zone of a volatile memory of the computer, downloading an unlocking program from a downloading tool to the volatile memory, the execution of which generates the calculation of a second value from the first random value and from a determined relation stored in the unlocking program, and writing the second value into a second zone of the volatile memory of the computer, reinitializing the software of the computer without erasing the first and second zones of the volatile memory of the computer, comparing the values stored in the first and second zones, unlocking the anti-starting system of the computer, if the comparison is successful.