Sometimes it is necessary to apply a switched 12V voltage. This is necessary if the radio always stays on and does not switch off automatically. For vehicles from year of construction 2009 this is not necessary if you have a custom fit car radio. Because these radios come with a CANBUS module, and this CANBUS module has a switched 12V connection.
We have made a video in which we show you how to find a switched 12V in your fuse box.