I bought a second hand BMW 5-series about a month ago, and I noticed something odd. When I was speeding on a motorway abroad, there was a signal right before a bend that displays the speed you are travelling at, and I could see it worked on the car in front of me but it didn't display anything when I drove past.
I thought nothing of it until a similar thing happened elsewhere, a warning for other cars, completely blank for me...
How can I find out if the previous owner had a scrambler installed and 'forgot' to tell me?
Thanks a lot