Method for providing access to one or more transponder functions of a transponder mounted in or on a vehicle, at least one of said one or more transponder functions comprising transmitting a signal comprising a transponder identifier to a receiver of a timing system that is configured to determine the point in time that said transponder passes said receiver, said method comprising: establishing a communication link between said transponder and an access module configured to determine time information comprising an indication of the current time, wherein said access module is implemented as a secure hardware device that is removably connected to the transponder via a wireless Bluetooth, Wi-Fi or near field communication interface or a wired data bus, preferably a CAN bus; sending a transponder identifier to said access module; receiving encrypted rights information from said access module, said rights information being determined on the basis of at least part of said transponder identifier, said rights information comprising one or more access conditions for determining when a user of said transponder has a right to access at least part of said transponder functions; a cryptographic module in said transponder decrypting said encrypted rights information on the basis of a decryption key that is stored in a secure memory of said transponder; storing said decrypted rights information in said secure memory of said transponder; determining said rights information stored in said secure memory of said transponder; receiving time information from said access module; determining whether said user has a right to access at least part of said one or more transponder functions on the basis of at least part of said access conditions and said time information; and, a microcontroller in said transponder configuring at least part of said one or more transponder functions in accordance with said rights information if said user has a right to access said one or more transponder functions. establishing a communication link between said transponder and an access module configured to determine time information comprising an indication of the current time, wherein said access module is implemented as a secure hardware device that is removably connected to the transponder via a wireless Bluetooth, Wi-Fi or near field communication interface or a wired data bus, preferably a CAN bus; sending a transponder identifier to said access module; receiving encrypted rights information from said access module, said rights information being determined on the basis of at least part of said transponder identifier, said rights information comprising one or more access conditions for determining when a user of said transponder has a right to access at least part of said transponder functions; a cryptographic module in said transponder decrypting said encrypted rights information on the basis of a decryption key that is stored in a secure memory of said transponder; storing said decrypted rights information in said secure memory of said transponder; determining said rights information stored in said secure memory of said transponder; receiving time information from said access module; determining whether said user has a right to access at least part of said one or more transponder functions on the basis of at least part of said access conditions and said time information; and, a microcontroller in said transponder configuring at least part of said one or more transponder functions in accordance with said rights information if said user has a right to access said one or more transponder functions.