Monitor allowed in the car???

Tach schön!! since last week I had a dvd player with external monitor in the car and let ́s just run music videos!! on Sunday it was so far, just came out of the disco and see blue light behind me! the first thing I did to get out of the way was tell the monitor!! the policeman then only meant like this: ah ha the distance is already out!!? when I asked her about the control then what this looks like legally with monitor in the car they only meant that they have not yet occupied themselves with it!! (does everyone like him??) it should not distract the driver!! have nowhere found anything to do with it!! I can also have the tittels displayed or possibly with navi in de irreschiocken!! at the things the monitor goes out even during the ride ni, and must be visible to me! only eats jetz forbidden to be able to see “moved pictures” or is that in my measurement when I touch it?? *ratlosbin* mfg Marco