That's if you set both switching and sensing to the same pin.
octoprint (4).log (227.8 KB)
there its set on internal but it doesent work...
No error but no switching
I realize this. You're going to need a multimeter to verify the GPIO pins are working correctly.
Okay, thanks.
Its not the code... It switches from 3,3 to 0,16
But why doesnt it turns off? Any ideas? Bad Relays?? Link to a god one??
If I disconect the signal wire it turns off 
I've found that many relay modules claim Pi compatibility but end up only working with 5V logic levels. It's kind of a hit or miss thing if you're buying from Amazon or AliExpress.
The solution is cibfusing but it works. I switched to high level logic (5V).
The Relay is still triggered from 3.3V but doesnt react on the 0.15V.
Thanks for the Help.
That's why I asked before. HIGH mode works 3-5V.