Abstract: A tire monitor sensor (16) for a vehicle has a sensor (26, 28) being adapted to measure a condition of a tire of a vehicle, a control unit (24) being connected to said sensor (26, 26) and being adapted to obtain a condition value (C) for said condition from said sensor (26, 28), said control unit (24) being configured to transmit said condition value (C) wirelessly, and a power source (20) providing electrical power to said control unit (24) via at least one terminal line (36, 38). Said terminal line (36, 38) is orientated with respect to said control unit (24) and configured to also act as an antenna partly, said control unit (24) being capable of transmitting said condition value (C) wirelessly by means of said terminal line (36, 38). Moreover, a tire monitor system is shown, said tire monitor system having a tire monitor sensor (16) and a receiver.