CAN (Controller Area Network) BUS is a computer system which provides rapid information flow between various functional units in the vehicle. Instead of myriads of wires, signals are transmitted from a single data collecting and management unit. Signals indicate that, for instance, ignition, automatic gear, anti-block system (ABS) or anti-slip regulation (ASR) is in operation. Because data is transferred on a single cable, fewer electric connectors are needed, which indirectly reduces the number of possible failures. Our tracker can read (digitally coded) messages in the CAN-bus network, and convert them into traditional analogue signals.