When you mount a new radio, it is important that the new radio turns on and off automatically with the contact. Usually this is also the case but for example with a Volkswagen Golf 5 it is always necessary to pull an extra wire from the fuse box, before we start pulling a cable first try the easy solution which usually helps.
On the photo below you see 3 plugs. Usually the radio is delivered with plugs 2 and 3 connected to each other, disconnect this and connect plugs 1 and 2 with each other. Then test whether the radio turns on and off automatically. The radio should go out when you remove the key from the ignition. If the radio automatically goes out then you are ready, unless you have a Volkswagen Golf 5 or Volkswagen from the same year, then it is necessary to pull an extra cable from the fuse box, see video link: YOUTUBE
After you have pulled a cable you must disconnect all connectors 1,2,3 from each other. The cable that you have drawn must be connected to the RED, and ORANGE wire of plug 1. Now the radio and the lights will come on when you switch on the ignition, and go out when you remove the key.
Finally you cut the YELLOW wire that runs from the Quadlock plug to the CANBUS, you see this wire in the photo.