I rebuilt my poly61 endcaps, so I removed the main and voice boards, reassembled the thing back together and worked fine. Afterwards I decided to replace all the tact switches, it worked fine turned it off. About 2 months later, turned it on and the assigner board and programmer boards switches are unresponsive, the displays constantly shows P5 / 61 and won't respond to any pushbuttons. The PSU +15/-15/+5 volt rails are good. Both programmer & assigner boards have voltage, checked all transistors and diodes and are good on both.
Has anyone seen this type of problem before? could it be a CPU board issue? Looking at the prints, I can't seem to find whats common to both boards?
anyone has any ideas?
thanks in advance