I have a Funhouse (Actually, 2 of them). Had a lot of problems with getting #1 up and running, but finally got it going - mostly. The ONE remaining problem is that the START button doesn't work. Also, the plumb bob doesn't work. New Rottendog CPU board which works perfectly in the 2nd Funhouse. Swapped the coin door interface boards - BOTH work in the 2nd machine, neither gets the START button working in machine #1. Flippers work fine. Coin door control switches work (all 4). ONE of the coin door coin drop switches works, the other no (could this be a clue to the problem?). Unplugging the coin door has no effect on the START button working or not. Switch is fine and connected properly and tests OK both normally closed and normally open. Have checked the wire connectors to the coin door interface board and they seem OK. IF ONE WAS BAD, which pin(s) would they be? One odd thing that's possibly related is that when in switch edge test, the ALWAYS ON switch randomly comes on and off. I know this switch is on the coin door interface board, but jigging the board and the plugs does not cause the ALWAYS ON switch to deactivate/activate. Have tested the continuity from the switch to the board through the board to the backbox and it buzzes out OK. I've probably spent 10-15 hours with a buddy of mine trying to figure this out with no success. Anyone ever seen this before? What was the problem/solution?

*******************
FOUND THE PROBLEM: Battery on the MPU board had dripped just a bit on the cabinet switch plug/header directly below it. An almost undetectable amount of goo had worked it's way into the inside of the plug and caused it to not to connect to the pin. Using a alligator clip with a diode and jumpering the two START BUTTON pins caused the game to start. Running a wire from the START BUTTON switch directly to the pin caused the start button to work. So the problem WAS in the connection between the coin door circuit board and the MPU. Thanks to all who offered advice.