Rolf,
with all due respect, we get that you know how to read schematics and enjoy trying to describe the circuit to those that are not familiar with them or don't understand them. The majority of those you attempt to help here are not getting your circuit descriptions. You need to tell them how to fix the problem.
When I deal with an EM problem, I usually have it repaired in less than ten minutes, start to finish from a closed up machine. This is where experience really comes in to play. Note my earlier post. That's where I feel the problem lies. Since the OP may not have a clue on what I meant, I will post an exploded view of the assembly from the Williams Parts Catalog.
The wiper switches (eleven of them) are SW-01A on the drawing. The disc, that is likely filthy and maybe even worn out, is B-7470 on the diagram. The 12 switches, one for each spot/hole on the wheel are part SW-01M on the diagram. To access any of these, you disassemble the unit from the bottom of the playfield.
Note how the OP only sent a pic of the top of the playfield. As Otaku questioned, the OP may not even be familiar with how to lift the playfield up. If that's the case, do you think he even has a clue what any of the switches are that you have highlighted? Just the simple ones on relays or the wheel holes. Then you can have fun describing the score motor switches.
The OP would be better off paying someone to come over and help him repair the machine. Otherwise, if he breaks something on that wheel assembly that is unobtainium, he may not be able to have the wheel functioning properly ever again.
The OP should list his location so someone close could offer to help. This is why I am not bothering to mention how to clean the switches and contact disc. That is way beyond the scope of a simple post. Hopefully, the OP is mechanically inclined and can clean a dirty contact or two... dozen.
Greetings, MrBally
Fan Tas Tic wheel assembly (resized).jpg