We have a Korg C30 that still sounds fine. But for as long as I can remember, the pedals (there are two) haven’t worked.
Anyway, if there are any pointers to what it could be or what to check inside (I’ve never disassembled it). I’m hoping it’s a “oh, sounds like you need a new such-and-such, here’s the part number!” But not holding my breath
Remove the connector that comes from the pedal unit, then short out all the pins in the unit (no fear you can’t break anything). Now turn on the instrument and see it it works.
If it does work - then problem is in the pedal unit or the cable (the easier version) if it still doesn’t work then we have to have a closer look inside the unit.
But first thing first.
Looks like the cable running through the leg of the stand to the base of the keyboard is continuous…
There are 3 wires (white, red, brown). Used an old ohm meter to test, and each was continuous.
This pedal stand has two pedals, left and right, no middle pedal.
On the base of the keyboard, when I short red and white pins, the sustain works. Shorting brown and white does nothing. (Nor does red and brown shorted). Unless one of these combinations is the soft pedal effect, and I’m just not noticing it.
So, either connectors are faulty (at the keyboard side or the pedal side). Or the pedals aren’t working.
Are the pedals just switches to mechanically short out the connections? Or is there a circuit board getting power that electronically does the work?
top side of connector wires from pedal stand
The square peg by itself is the brown wire endpoint
The square peg on the corner is the red wire endpoint
The round one is the white wire endpoint
There is a little circuit board underneath the pedals - I suggest that some of the circuit board tracks have corroded. You have to take the circuit board out (may be a little tricky) and trace each track according to the little diagram above. If you find a break, use a piece of thin wire and solder bridge the break. If the break is underneatch the rubber contact then it may not be fixable that easy - if at all.
Take that rubber contact off - gently pull it off and then clean underneath with methylated spirits. Then put it back in. You need a soft wire that is not pointy so as to not puncture the that little leg (I use a 5W resistor - works perfect)
To test a fix, I put double-stick tape on the end of the pedal part that should push the button. Then cut a small piece of soft foam and stuck it on there. It worked … extending the pedal “button pushing” part with a little bit of foam allowed it to push the buttons enough to work.
I’ll still do the cleaning maintenance you recommended. I have to disassemble again anyway to make a permanent fix.