Concert A-151 piano pedal

[flora.iton]

Hi,
I have a Korg Concert A-151 piano but no pedal to match it.
It's a rare limited edition Korg.
I got a PU pedal that plugs into the port but it is reverse polarity, IE the sustain turns OFF when u press the pedal.
I don't know what to do. How can I reverse polarity either in pedal or piano? Everything seems to connect directly to the motherboard.

Seems like the easiest thing to do would be to find an original pedal from an old A-151 piano.