Failure of one of the braking system circuits
If the brake fluid level has dropped below normal and the free travel of the brake pedal has increased, this indicates that one of the two brake circuits has failed.
The remaining active circuit allows you to stop the car, but more force is required when pressing the pedal, and the braking distance will increase.
For your safety, if your brake system is faulty, please contact a BMW service centre as soon as possible.
If the display shows the message "Bremsbelflge" ("Brake pads"), this means that the brake pads are worn out and should be replaced as soon as possible.
Attention: Replace at a BMW service station and use only brake pads approved by BMW. Otherwise, driving safety cannot be ensured and, in addition, you will lose the right to warranty service.