Thanks for all the replies. santa2 Removed the unit now from the car (2006 /+4). However, I still don't know what it is. Ebay is full of such devices but without clear description what is does. Most likely it is some kind of tracking device. The red & black wires are connected to the battery, the white one seems to be an antenna. It consumes about 40mA and certainly will drain the battery if the car is not used for a longer period. If disconnected from the battery the unit will survive for some time using the internal battery.

Cheers, Peter

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