Constantly updating the map of your BMW is crucial because roads keep changing every day. For example, two-way streets can become one-way, and new roundabouts can come your way. The process of updating your map is easy. You should use a DVD or USB device to complete this task. First, you should download an updated version of the map in the BMW database. Then, plug in the USB or insert the DVD with the new map into the drive. You will see the screen will automatically switch to the navigation update tab. After this step, you will have a seamless process, but always remember to leave your car running until the update completes. The update should take about twenty to thirty minutes.