Quoted from Doomer:After the first ball, ball kicks out of out hole rolls over trough switch target bank resets O & P relays fire but game stays in first ball. Player unit coil does not fire ( it does fire on start up)
Starting with the highlighted switches on Z1, Z2, BX, P, and U:
Inspect and diagnose this circuit with Alligator clip jumper wires
https://pinside.com/pinball/forum/topic/gottlieb-big-shot-repair#post-6305153
http://www.planetimming.com/Pinball/troubleshooting/EM%20Troubleshooting.pdf
http://www.pinrepair.com/em/index3.htm#features
Example of a pinsider actually doing this https://pinside.com/pinball/forum/topic/red-baron-tech-question#post-5858156