Quoted from paulace:

Have you used a piece of jumper wire before to help troubleshoot? That would probably speed things up, if you're familiar with how to use one to short various parts of the circuit to eliminate switches. For example, if you hooked a jumper between the 2 points marked with purple X's below, and then the machine worked correctly, you'd know the problem was with either Z1 or Z2 - the switches you had shorted across and taken out of the equation.[quoted image]

Quoted from Doomer:

Okay this probably a stupid question. How do you jump a motor switch? What does P2G P3G indicate on the schematic.
Thanks
Frank

Quoted from paulace:

Hey Frank,
Power (or electricity) doesn't come from the coils. Coils are just what they sound like - coils of wire that don't do anything until electrical current passes through them. Then a magnetic field is created and that field pulls in a metal plunger or pulls a metal plate to do work - eg. make a flipper move, make the player unit step up one time, pull in a relay armature, etc.
There is a voltage differential between the 2 sides of the transformer (another more descriptive name for voltage is "electro-motive force" - it's an electrical force that "pushes" electrons through a conductor. If you think of the analogy of water going through a hose, voltage is the water pressure, current is the actual flow of water, and a narrowing or kink in the hose that resists the flow of water could be resistance.). On the schematic, if you trace the wires from both ends of the transformer, you'll see that the wires travel up vertically on both sides of the 25V section of the schematic on the right, and the 6V section on the left. If you trace a path between the 2 vertical wires, through any coil, and through all the switches that are in series with it, the job of those switches is to turn on the coil in certain conditions by closing and allowing electrical current to pass through the coil, which turns it into a electro-magnet and allows it to do work. If a coil isn't turning on (having current pass through it), then either the coil is burnt open, there's a bad solder joint, a broken wire, or one or more of the switches aren't closing or making electrical contact when they should. By jumpering, you're trying to narrow down the area where the problem lies. Then usually, you have to get in there with your eyes and see what the actual problem is.
I'm sure there's a much better description of basic electrical behavior out there - MarkG is always very helpful and could probably steer you to one - in fact, he has a great site that you should probably look at that explains these things and how they're related to pinball very clearly (https://www.funwithpinball.com/) - plus it's just fun to go through! It would be a good idea for you to read a little about it - it makes troubleshooting easier if you understand the big picture of what you're going for. And you don't have to be an electrical engineer to work on EM's....just have some basic electrical knowledge and be able to think logically.
Good luck!