If your BMW throws the warning saying “Reduced Driver Assistance”, it may mean almost anything connected with the adaptive cruise control system: the camera behind the interior mirror, the radars behind both bumpers, various connectors, steering column system, etc.
But, you may want to start checking this problem with the issues that you can fix on your own without any extra costs. In this video, I will tell you everything I know about this problem with the Driver Assistance systems in BMW cars and will give you several tips on what you may do to fix the problem.
Unfortunately, in a lot of cases, you will not be able to actually fix the issue on your own. If your car is still under warranty, try getting it to the dealership while the warning is still on (don’t turn the car off), otherwise, it will be hard to diagnose the problem. Also, I will tell you about the most common culprits of this warning to give you ideas on where to look.