Hi Sean
I talk as we'd have an "Fashion Show" pin to troubleshoot (so look-up the colors of the wires in YOUR schematics).
Toggle-off the pin and unplug the main power cord (Safety Reasons). Look the wire running from transformer "HOT" - wire-color-red-yellow to 25-Volt-Fuse. Then wire-color-red-white runs away from the fuse into the pin. Then come the mentioned switches - then the connection runs further as wire-color-red-mingled-with-white. (Look in Your schematics --- look for a switch that is obviously on the playfield) I choose "Slingshot-Switch has such wire-color-red-mingled-with-white soldered-on".
I establish*** an permanent jumpering. Then I plug-in --- I am ready to immediately toggle-off the pin if something strange is happenning - toggle-on and start a game then I try the flipper bats and the bumpers - everything.
I assume: All connections withing the playfield are good --- so when I jumper from the fuse to "someplace on the playfield": Everything on the playfield works - works the same.
I establish*** an permanent jumpering: Better would be: Having a Jumper-Wire that has a SWITCH in the wire --- we could establish (pin is toggled-off and main power-cord is unplugged) the permanent Jumper with its switch OPEN - then plug-in, toggle-on, start a game --- THEN close the switch in the Jumper-Wire. Doing so we would be very close to "reality in a running pin".
The way I suggested it: Simple Jumper-Wire (with no switch) is good --- we must be ready to toggle-off when the pin does not like a permanent connection during reset as in a functioning pin the connection is cut --- so Your pin may act strange --- not resetting or other strange stuff happening ---
99.9% chance: We can do this test with a simple Jumper-Wire (with no switch) - and the pin does not act strange. Greetings Rolf
0Fashion-Show-Work-04 (resized).jpg