Back onto my biggest challenge again tonight, Hot Tip. Haha

I pulled the Jones plugs out of the head and turned the machine on with the playfield down, but the score motor continued to run.

I put all the plugs back in and turned the machine on again. Score motor still runs continuously. I then put the Bonus Unit back to zero and the score motor stopped. So, every time the bonus unit increments from the zero position, the score motor runs continuously. It's a switch!

At least I don't have to worry about something unknown in the machine.

Cheers!
Adam.