It sounds like either the actual contact is stuck in the ON position within the switch, one of the IG00157 ICs on the tone selector board has gone wrong or a short somewhere in the circuit for that switch. If either of the first two you'll need to source new components from somewhere, either from a broken CS-80 or one of the E-series electone organs with the same illuminated preset switches. I believe they also use the same preset ICs.
--- In yamahacs80@yahoogroups.com, "theblackbutterflygang" <theblackbutterflygang@...> wrote:
>
> Hi Folks,
>
> I'm the proud owner of a CS80. She is in lovely condition but has developed a quirk and I could use a little in fixing it. The panel 2 button is "stuck" on. The button moves freely but the presets are engaged only when held down. Any help here would be wonderful.
>
> thanks,
> Ian
>