Is the Tilt Hold Relay (R) energizing and staying energized?

Is the Score Motor just running continuously after pressing the replay button then?

Ok, then that would be consistent with AX not activating to continue the startup sequence, or else all the score reels are already reset to zero and so it considers the startup already complete.

If there are points on the score reels, then do they reset back to zero? (even on player 1). Can manually step some score reels to put them off of zero to try. If the score reels are not at zero and don't reset, then that's also consistent with AX not activating.

Another thing to check is that DX is latched. If it's not in the latched position, the path to AX will be open.

Still curious to know if the score reels reset, and whether DX is latched.

This is great then. DX would normally be latched after some points are scored, and stay in the latched position until the start of the next game. So if the game got powered off while DX was unlatched, it won't be able to start a game again.

So now the question is, after you start a game and play it (scoring some points), is it able to start OK again?

OK, then that means DX isn't latching when points are scored. So to confirm:
- you manually latch it
- start a game
- DX unlatches
- score some points
- DX should latch, but stays unlatched instead

That would then suggest the path to DX is open somewhere, or the latch coil connection/coil isn't working. I'll have to check the schematic tonight, but in the meantime, could check for any loose wires on DX (there's at least one switch on DX that needs to be closed to latch it). There will also be a switch on N and M (points relays) that cause it to energize and latch, but the switch on DX would be common, so if no points value causes it to latch, then I'd suspect the switch on DX (but need to see what else is on that path on the schematic).

Cool, thanks. So that normally closed switch on DX itself would be my first suspect. Then the normally closed switch on R (which will be closed when the game is first powered on, but before the R relay is energized), and the one on H. Or the coil itself.

Once R and H are both energized, then the only path to energize DX is through N and M, and that normally closed switch on DX. So a quick test would be to reach the point of R and H being on (and those switches open), and then activate N and M. If DX still doesn't energize and latch, then it's either that DX switch or the coil. (Remote chance of a Jones plug too I suppose, but we'll ignore that for now.)

But a short list of things to check at least.