Hi Pinside,

I have a switch issue with ST:TNG and am hoping you can figure it out because I am out of ideas. The game constantly put balls in the shooter lane. After hours of troubleshooting i found that switches #32 (Under L. Gun Sw.2), #42 (Under L. Lock Sw. 3) and #82 (Rift) all don't work. They are all in the same row #2. All other switches I tested worked just fine including others in row 2. I tried a know good xmit opto (it works with another opto receiver) and and soldiered in a spare receive opto for switch #32 as that was the first switch I saw out so I decided to start there but it didn't make a difference. I re-seated all cables on the cpu board and opto board under the play field with no change. Any ideas on where to start looking?

Thanks,
Brent

I've performed the switch matrix diagnostics at http://pinwiki.com/wiki/index.php?title=Williams_WPC#Switch_Matrix_Problems
No issues were found. Every individual switch turned on/off. I assume that means I can rule out the CPU board as the issue?

Thanks Marc! I figured it out.

I did have 12 volts and I started tracing the wires on row 2. I found there was a loose wire on the "left bank middle" switch #52. There was very little soldier to begin with on that part of the switch, surprised it held together for as long as it did.