Casio CDP-100 keyboard piano dead keys - PCB issue?

Thread Starter


Joined Jan 4, 2020
Hi all,

Newbie to both this forum and electronics! I have a somewhat old Casio CDP-100 with 8 keys that went dead recently. All other keys are fine and speakers/power are working perfectly.

Schematics here: CDP100 service manual.pdf

Since my dead keys are F3-C4, it looks like from the circuit description on page 3 that the issue is the F14/S14 line. I opened up the keyboard and have been looking at the MAIN PCB M403-MDA1 (manual page 17) but not quite sure what I'm looking for. Any advice? Am I looking in the right place? Any obvious fixes here?

Attached front and back pictures of the MAIN PCB in case anyone can visually see any obvious damage.

Thank you!IMG-8611.jpgIMG-8610.jpg


Joined Dec 29, 2008
Occasionally, moisture of some type, even atmospheric humidity can invade wire contacts or possibly push buttons, and reduce performance. It is not a sure thing, but try carefully removing headers and similar connections followed by spraying both sides with electronic contact cleaner. Allow time to evaporate and dry, then reassemble. Don't bother with sprays like wd-xx or whatever. Try to locate the actual contact cleaner spray. It should be available at the local H.D. hardware department.