An arrangement for providing redundancy in a vehicle electrical control system, comprising a plurality of electronic control units connected to each other through a first data bus, and where each electronic control unit is connected to one or more I/O-units through a separate second data bus, where each second data bus is provided with a separate transceiver which allows communication between an electronic control unit and an I/O-unit, and where the arrangement comprises a programmable switch arranged between the electronic control units and the transceivers, where the programmable switch is adapted to interconnect each transceiver with a selected electronic control unit. The advantage of the invention is that it allows a transceiver to be reconnected to a new ECU in an easy way, when the ECU to which the transceiver was originally connected to breaks down, which allows the new ECU to access the I/O-units of the broken ECU and which in turn provides an effective redundancy for the electrical control system.