Response from Jonathan: Pete,

It sounds like this issue could either be related to your wiring or a problem with your ROM board. We recommend starting off this repair by making sure that all of your coin door switches and buttons are wired correctly. Check to see that each one has two wires going to it (one for the correct input to the board and one for the ground) and that they are attached to the correct wires on the ROM board. You can look up the locations and wires on the Cabinet Wiring Diagram page in the manual (it should be the last page). You will also need to check that they are making a good connection. You can do this by using the continuity check on your multimeter. Check out our post on Checking Fuses With A Multimeter for more information on this multimeter setting. Basically you just place each of your multimeter probes on either end of a wire and it should tell you if the wire is making a good connection.

If you continue to have problems after double checking all the wiring and the connections then you could have a problem with the ROM board itself. Start off by making sure that their are no cold/cracked solder joints on the board (especially on the pins where the wires come in). It is very common for boards this age to have multiple broken solder joints. You might need to touch up the solder on these joints in order to restore the connection. Other than that, you might check out our post on Inspecting An Arcade Board for some great tips that will help you hopefully get your board working again.

Hope that helps. Thank you for your question and good luck with your repair.