Cleanded mine twice and it didn't fix my problems. I had brake light. traction control, and SES lights. My tracking headlights wouldn't track, cruise control wouldn't work, traction control was disabled, and start off assist wouldnt work.
When I driving the car once I hit about 20 mph the computer would reset everything and then it would come right back. It also reclears the codes randomly when driving and they always came right back.
Took it into bmw and they found it was a dirty speed sensor. All they did was cleaned it off and everything works great now. Been about 1000 miles with no issues. They didn't even charge me for the cleaning.
So if this great writeup doesn't work for your problem I would consider cleaning the speed sensors
'07 E90 MT Sports Package l RB Turbos l JB4 G5 with Race Backend Flashl AA CP, BOV, and IC l Modified Injen DCI l Raceland 2.5" DP's l M2 Dual 2.75" Exhaust l