How long does it stay on before it turns off? A few seconds? Is it the same amount of time every time you start it or does the length of time vary?

Is the hold relay energizing at all? What happens if you manually close the hold relay (with power to the machine)? Do the lites come on? Does it stay energized? If not, perhaps a switch needs cleaned. If it’s not a switch on this relay, can you post a view of the schematics that shows the hold relay circuit to see if something else might be cutting power to it?

I’ll admit that I am more familiar with older Gottliebs that only have a 25V hold relay that when manually activated will turn on lites. I assume the same would be true on newer Gottliebs, but don’t know for sure. Perhaps both hold relays on Paradise need to be manually activated to do this (e.g., the 110V hold relay provides power to the transformer that is needed for the 25V relay to have power).

I also assume though that the hold relays on Paradise should energize during startup. Are they energizing and staying energized when you press the start button?

And seeing a schematic could help diagnose the issue further. I’m not sure if you have access to one and can get a few photos, but this could help diagnose this.

I had this on a 2 player Mayfair. It would begin the start process and the reels began to reset but would often stop and go into Tilt mode. Sometimes it progressed so the reels zeroed and once the reset relay bank fired it did the same.
It turned out to be the kick off switch needing an adjustment to make the switch blades tighter. Because it had been playing up, the contacts had been arching a little to make them harder to made a decent connection. So a quick clean and adjust and it was fine.

Based on the schematic, when the replay button is pressed relays k, e, and w activate/close through various NC switches which closes NO switches on the k and w relays which each can then complete the circuit to the transformer (the part of the schematic you circled). Via the 25V circuit from the transformer, the hold relay, r, should then energize/close which will close a switch on a MB sw on this relay and then when k and w relays are opened again, the circuit to the transformer is then completed via a sw on the r relay (again, in the part of the schematic you circled). I am guessing that the k and w relays are on the relay bank that is reset during startup (are they? And does the relay bank reset during startup?). And so if this is the case and the r relay is closing during startup, your problem could be that the r relay mb sw needs adjusted, cleaned or one of the wires is loose (hopefully just at the switch).

If this is the case, then the startup procedure should be stopping more or less at the same place every time.

And if manually closing the r relay does nothing (no lites come on), this suggest that there’s something wrong with the circuit that should be completed when a switch on the r relay closes.