So the game was playing fine until..... I pressed replay, the game reset all scores correctly and then the score motor just kept running and no ball kicked out. After a bit of exploring I lifted the ax relay to check adjustment. All looked fine so replaced it. The game started fine and all was well. I then decided to adjust the centre top rollover as I noticed it didn’t always score. I then restarted the game.
It restarted correctly but once the scores reset player one started scoring 100 points repeatedly. The ball did kick out so the reset appears to complete successfully. The problem seems similar to the original but with scoring now too! I’m guessing it could be the same dodge contact maybe related.

On investigation the 100 relay is being pulsed by motor 1c switch scoring 100 in groups of 5 continuously. Removing the motor service jack obviously stops it but if you move the motor by hand the scoring continues as switch 1c is pulsed. If I pull the rear plug from the playfield to the bottom board it stops. I guess this suggests a closed switch/short on the playfield, however I can’t find it. The fact that the motor is running I guess suggests it’s not a simple 100 point score but a 500 point of similar. I’ve check all the switches, including obviously the one I adjusted but can’t find anything dodgy. I also can’t find any relays such as bonuses on the playfield that are stuck on and I’ve also check the switches on the bonus unit and varitarget. Any clues how the track it down? I have no info on the wires in the socket on the playfield that I can disconnect to stop this - if I did it might help me identify which circuit was triggering it maybe?

Any suggestions on how to proceed to track it down? Thanks

Thanks guys. Sorted! I wasn’t sure it was the 500 pint relay but your comments put me back there and confirmed it was indeed being locked on. That made me pursue the rollovers more diligently. The blade support on the centre rollover was bent in a banana shape but was hidden from view by other playfield bits. A more careful look with a torch showed that while the end was gapped ok the hidden middle bit contact all the time. And quick straighten and all good.

I be told myself again and again not to believe in coincidences as my experience they rarely happen. Having adjusted that I should have gone back there more carefully.

Thanks guys.

As a follow up. Soon after my post above the original problem returned - the score motor not stopping running at the end of the reset cycle. A quick look showed the lock on the AX relay wasn’t releasing. Or rather sometimes it would and sometimes it wouldn’t. When it wouldn’t it appears to be weakly trying and not succeeding. This was tracked down to motor 4c switch which when cleaned solved the problem. All good.