“Also zusätzlich zum D2 die ich schon angelötet habe muss ich noch die S4, 5,6 mit verbinden, richtig?”
Yes because you did not hook the LED to the 3PDT Wiring Board.
The foot switch is what tells the pedal if it is On or Off. Since there is no LED on the Foot switch then you have to make the wire connection or wire and LED to the foot switch. If you wire an LED to the foot switch do not forget the CLR first (Current Limiting Resistor) anything from 2k to 4k7 will do.
I still cannot follow the wiring. You will need to manually make sure all connections are correct especially regarding the Input and Output Jacks. If there is no sound in Bypass Mode then it is wired wrong.