A couple of quick things... can you manually start the score motor and see it finish ist rotation? If it does then your 24v line is good. If not check fuse etc.

next step manually press in the tilt hold and hold relays, you may have to do them together. If they wont say engaged then you have a slam switch open, door, bottom board, head. If they do then you should be able to start a game with the start relay...

yes, a third rotation is a full cycle. its a quick check on the 24v feed.

It is normal to have the tilt lit when you turn on the game. Is it set for freeplay, if not are their credits?

and depressing the start relay gets you past the credit stuff

If pressing the Replay button doesn't activate the Start relay (S),
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

pasted_image (resized).png

I'm much better at schematics than when I started a couple of years ago, but some things still are confusing.

In post # 8 I can see that the "anti-cheat" switch, motor 2B, 1C and all the others in the (red) path are closed except for the replay button (as expected), but why is the zero pos. "ball count" unit open on the schematic? It would have to be closed for the path to work.

Are we to assume it will be closed by some other action - like when the ball count unit resets to zero on start up? ...but we haven't started up yet. But then I remember the fact that the schematic shows the game state as started but then unplugged. Hmm - have I answered my own question? The switch is really closed since the ball count unit would be at zero (switch closed) when a game ends as the last ball drains, but the schematic shows its state as game started/unplugged, switch will be open.

Still, it's confusing to have the schematic show one thing, but some switches in reality are in the opposite state. Is there some way to make clear which switches are supposed to be 'wrong' on the schematic besides carefully thinking about each one and considering what state they are really in at game start vs. game started then unplugged?

I think that "Zero Pos. Ball Count Unit" switch is supposed to be closed on the schematic - it's a little hard to tell on that copy.

Volley (resized).JPG

But you have a valid point about some switches being opposite of how they're shown on the schematic. For example, the "Zero Pos. 'Replay Unit'" switch would have to be closed to start a game, yet it's shown as open because, once you've started a one-player game, the Replay Unit drops the credits from 1 to 0 and the switch opens. Sometimes the interlock or latch/trip relay switches will throw me off for a bit - have to remember what state they're in when the game's started. Not sure how they could have made things clearer without making the schematic a lot more confusing... You just have to think of it as part of the fun of figuring out these circuits!

Thanks, Paulace. I do see that 'closed' slash under the red line when I zoom in. And I missed that the zero position replay unit switch was also open. Your explanation makes sense, I just have to concentrate and think when I see impossible open switches and how they might be closed when starting up vs started/unplugged. Experience will help the most.