Fc4 sustain pedal is in "sustain" mode at all times -- it won't release the sustained notes. I tried plugging the pedal in (to a roland ep-9) before powering up and had the same problem.

No you can't as our PROPER Expert Cindy says.

Casio Ct-636 does not support any sustain pedals.Amazon.comhttps://www.amazon.com > ask > questions
A: Casio Ct-636 does not support any sustain pedals.

The other 'Contributor' probably saw this

CT-S1000V - SupportCasio https://support.casio.com > manualPDF

This Digital Keyboard does not come with a pedal unit. • You can use the PEDAL1 jack to connect an optional (SP-3, SP-20) sustain pedal. You can use the.

Yamaha FC4 and FC5 sustain pedals are normally closed, sorry Fred. Roland is opposite. I suspect the P120 just needs to be reinitialized. Hold down top white key (C) while turning on power. Wait 3 seconds and then release white key. Should now be reset to factory spec. Always plug the pedal in before you turn it on. If it still doesn't work check it with a meter.

Press Utility and scroll (up/down arrows) till you see FSTxCtlNo and press inc/yes until it says 64. Your sustain will now work. Hit exit to get out of edit mode.

You should try having the pedal connected when you turn unit on. Some pedals can be rewired to act opposite... However I believe this pedal should work with the Casio. You can open the pedal and see if you can move one wire so it works opposite. Also verify that the jack is set to the "SUS" setting per your user manual... around page E14

You should have a setting on the keyboard which allows you to switch pedal control. Check the manual.

every sustain pedal got different polarity.. normally just go to global setting on your keyboard and change damper polarity setting to plus or minus (select which one work with your sustain padle).

The function setting is for the PANEL sustain (Page 68 of your manual)

The other method of sustain is by footswitch or pedal option. See page 13.

If you use a footswitch, it needs to be a normally open contact type. If you plug a Roland type in, it is opposite polarity and will sustain UNLESS the pedal is pressed. Make sure nothing else is plugged in the sustain jack... headphones that are inadvertently plugged in there would sustain.

1.Make sure you are plugged in to DAMPER (not FC1 or FC2) 2. Check to see if the notes STOP sustaining when you PRESS the pedal. If that is the case, first try turning off the Roland with the pedal plugged in and restarting with the pedal pressed down. 3. Press the EDIT button and scroll to Damper Polarity. See if it's set to Standard or Reverse. 4. If problem persists after all that, try holding the pedal jack into the Roland at different angles and then try the same with where the cable connects to the pedal. At that point, you can either attempt to repair the pedal or get another one.
Hope this helps, Stewart

The Yamaha FC-3 uses a TRS (three conductor plug). The PX330 does NOT use TRS jacks for the sustain and sostenuto pedals so they are NOT compatible with the Yamaha FC-3. Therefore I would conclude that continous sustain that the Yamaha pedal would be used for is NOT supported.

I have the same problem, But I have been using the same pedal since new. Infact it came with this pedal. Then suddenly it started doing this. Could I have changed soem setting by accident?