42S won't self test or turn on after turn off (Problem Solved)

[Geoff Quickfall]

"When on, all keys work"

Got it, funny though, I had one that would turn on, function perfectly, but not turn off! It was the contact foam problem.

However, you have repaired the contact foam, and since the repair must be presumed to be perfect; it sounds like an IC problem.

Without, I assume, any electronic testing equipment available, I would re solder (quick melt of each connection) the IC's to rule out a cold solder. This might have ocurred when you disassembled the unit to repair the foam contact. Stressing the board could have caused the solder break quite easily.

Cheers