Thanks for helping out. This is the problem.
Fuse f105 blows in the game when the right flipper button triggers. Also it then fires a ball from the right popper into the launcher and then the machine.
Cause:
I soldered on the coil and left the machines power on, some weeks ago. Painfull mistake. A pinsider concluded that I shortened something via the tip. I resoldered today a brand new coil and and replaced a new fuse for F105.
Check the video what happens.
In the coil test the right upper flipper does not blow the coil, but it launches the ball from the popper into the gun. When I look closely to the F105 fuse, I see the line inside actually move when the upper flipper test is running. But it stays in working order and the fuse does not burn.
I restarted the game and as soon as I hit the right flipper the fuse f105 blows again. The ball pops again to the canon. The machine works again normal when I change the fuse untill I blow it hitting the right flipper.
What to do?
I did another check someone suggested. I soldered the two outer wires of the coil and left the black one in the middle. Turned the machine on an played a game. Hit the right flipper did not cause the F105 to blow.
Thanks again for your kind assistance!