This is done by adding extra hardware

You can make your car do almost anything by adding extra hardware

If you want the car to flash headlights, perform a light show and flap it's mirrors in and out when locking the car, you can do that too.

Or make the car blink every exterior light when you press the clock button on the nav - that can be done too

All you need is the extra hardware, programmed to do what you want.

That's what the Dietz module does - it monitors the clock key press and then sends an instruction to switch video sources.