Korg Poly800/EX800 Users

You need to trace the line that takes the keypad 3/tape enable/chord
memory button to the chip.
You will need a multimeter set to ohms x1. And then patience to
methodically work your way from the chip through the traces.
And you need to check to make sure that none of the switches on that
line of the XY matrix are shorted. If one of them is shorted then the
switches won't work on that line either.
If this is not something you can figure out with the schematics in
front of you then it might be time to find someone who can do it for
you.
/Mike
On Sun, 2018-09-30 at 05:13 +0000, zwright88@yahoo.com [korgpolyex]
wrote:
> Quite frankly that's a bit beyond my ability level - I have the
> schematics but no idea what to look for there.
> 
>