Ok, was having a root around behind the removable panels in the boot, like you do when you've got a new (to me) car.
Behind the drivers side panel, to the rear side of the fuse box, I noticed a wiring loom with a connector , not connected to anything, then I spotted the white box. It say
Siemens VDO 5WK10250C BMW 61.35-6 955 253. Now the simple solution would be to plug it back in, but it has'nt unplugged itself and i'm not sure if its the self distruct device.
Does anyone know what its for ?

i think its the control module for the tow bar electrics. ... - .- -.




Y. O. L. O.
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Yes it is the control module for the towbar electrics. Do you have a towbar fitted? if not it may have been removed by the previous owner... 06MY 4.4 V8 Autobiography Cairns Blue with Navy & Parchment Interior

Yep, theres a tow bar fitted, it has both the standard black socket and the caravan one. I got the detachable tow ball out and its never been used, if the opinion is that its the towbar electric module , i'll give it a go tomorrow.

Definitely the towbar module. I changed my looms to go from twin 7 pin sockets to the new 13 pin Jaeger socket. That's the box it plugged into.

Thanks fellas, i'll plug it back in and try a trailer board on it tomorrow.