nitrobonix

I have a E60 530D with a BMW tow system which I use with an Eriba caravan. My caravan is equiped with three stop lights. All the lights (car + caravan) are working properly except the stop lights on the caravan that blinks once then switch off when I brake. At that time the car displays an error message about the lights of the caravan.
Everything come back to normal when I disconnect the third stop light of the caravan. J went to my dealer in september, he said me that it is a known bug and that it will be solved with CIP 20.
He made the update on last Friday and the problem is still there.
As anyone ever seen the same problem ?

Many thanks for your help and advices !

new-kid

Not had this specific problem, but have often had a brief warning message about the brake light failure, which goes away again.
After much checking of bulbs etc, eventually prove this comes on even when the lights are working.

I assume (but don't know for sure) the warning is based upon a voltage sensing basis - hence why your extra brake light could be confusing the system.
A whizz electrician could probably slave switch the third brake light, taking the power from the extra caravan power supply. But frankly it may be simpler to just run with the two brake lights ?

pedrollo

I had a towbar retro fitted to an 02 E39, and even then the car electrical system had to be re-programmed to recognise the additional load. I don't know to what extent the car system has advanced but I would have thought that it would be software adjustable by the dealer.

If you give up on the car, try changing your third brake light to LED. The load is so small the car is unlikely to notice it.

Good luck.