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Hi, my piano is a yamaha clp 545, and a problem appeared recently which was the loud keys problem.
I decided to disasembly it so i can get to the rubber contact band and clean it.

Behind the keyboard was 3 part of the motherboard, I removed just the middle part because it's where the problem is (c,e and a medium)
when removed the mb i had to unstick the rubber band to it and clean it, so then I put back all the things back together but when played the mid part of the keyboard doesnt work or just work when being hit rly strongly.
I think i didn't put back the rubber back in the goodway, but the direction of it was the right one. so I just need help fix that please
As an observer “reader’ here of many members in the past posting of their DIY experience trying to fix the fairly common “ intermittent key presses - sometimes too loud or distorted /sometimes silent” phenom, i can safely say that i have never tried to do this procedure out of concern for a main caveat: after you do what you do to resolve the problem, you must put all the pieces back together the way they were prior.

I am one of those capable of taking things apart but not always good at correctly putting all the pieces back together 🥴

On the one hand, ive been impressed by the members here who’ve provided/posted details of their successes, on the other hand i can sort of commiserate with those, like you, who have not (yet) been successful 🙁 As such, if you really want to 1) fix the new problem you now have, and also 2) fix the original problem, you need to very carefully go back inside your DP and undo #1 at a minimum.

Ive seen members who had intermittent keys, say in the middle C octave, who went inside their DP and did the “cleaning” as you sort of described, but they also moved all the contacts (of that middle octave) to a different location and swapped the contacts there back to the middle location, after which they were able to put the DP back together and found their middle octave “fixed” ..... for a while, maybe months or years.

Good luck!
What do you mean by cleaning the rubber strip?

It has black spots at the bottom and they are a conducting coating which then short circuits traces on the printed circuit board to trigger the sound.

Some of the possible problems might be
- The rubber strip didn't go all the way in and isn't properly seated
- The black conducting coating was damaged if you touched it in some way
-Some cable is loose if you had to disconnect anything during the process
Please, let us know how and what products you used to clean the contacts, as what seems to me is that the conductivity of the pads has been drastically reduced
I just blew on it and passed a kleenex on it
And yes, I think it doesnt go all the way down because I didnt know how to do it even if I forced a bit
I will open it up again tomorrow on sunday so I just can show you guys and thank you
look carefully to make sure the rubber strip is seated properly. Doesn't a circuit board come down on it to hold it in place like in my yamaha cp33? Make sure everything is evenly seated ain't no big deal. Those contacts are pretty tough and I used rubbing alcohol to clean mine in the past. Just make sure they're clean and dry, Good luck MooganDavid

Kleenex leaves lint.

Lint is non-conductive.
I opened it again and here is the pictures:
Originally Posted by drewr
I am one of those capable of taking things apart but not always good at correctly putting all the pieces back together 🥴

I can barely figure out how to disassemble things, and have almost 0% chance of reassembling them correctly!

That's why I've paid the local Yamaha repairman $250 a few times over last few decades when my Clavinovas had issues.
Originally Posted by hablos

I can't appreciate any problem from the pictures, I would use some cloth to re-clean the metal contacts, soft soap and water to clean the rubber contacts (I use shampoo and a soft toothbrush) and be sure the circuit boards seat perfectly over the contacts. If that does not help, I would say next step is to replace rubber strips
I checked at the picture and it looks like a remote control. So here's my guess ,

They put some black graphite on the rubber. Graphite is conductive. When you push the key, the rubber make contact with the circuit board. If you push harder the second rubber make contact with the second circuit and the third one. They measure the resistance or the capacitance of the contact and it give a value of how hard you push the key. If you cleaned the rubber and removed some graphite, you will have to push harder to make any sound.

There is a few tips I can give you if you're good at fixing appliance. If not don't touch it !
You could exchange the rubber with another one, if the problem follow the rubber then the rubber is defective.
Note velocity is based on time between the staggered contacts making contact. There's a small difference, but enough to be measured by the electronics.

There are some ways to rejuvenate those black contact surfaces, like some graphite stickers or special paints and stuff, but I haven't used any of those.

(I once used aluminium foil on a VCR remote, but this is not a recommendation.)
Originally Posted by clothearednincompo
like some graphite stickers or special paints and stuff

I will try to get my hand on the graphite paint but what do you recommand to me doing with it
Just clean it properly, both surfaces with 99% isopropyl alcohol, re-fit rubber contacts onto the board first using the alignment lugs and holes (you could swap a high or low with the mid section to see if fault moves at this point) carefully reassemble ensuring cables seated, nothing slips or moves, and that should be enough.
Beware, alcohol will remove part or all the conductive coating. I would use alcohol only on bare metal parts (as the contacts on the printed circuit board) but not on the rubber parts. Those are better cleaned as I commented previously
Originally Posted by EB5AGV
Beware, alcohol will remove part or all the conductive coating. I would use alcohol only on bare metal parts (as the contacts on the printed circuit board) but not on the rubber parts. Those are better cleaned as I commented previously

I used isopropyl on both the rubber contacts of my ES8 and on the cabon contacts of the PCBs (printed circuit boards). BUT... I was extremely gentle when doing it. It solved the problems with loud notes, as far as I remember. (*) I second the suggestion on swaping contact strips to see if the problem is related to them or to the PCBs. Also, there are no mechanical fixing of the strips on the PCBs so there could be the case where the strips were displaced when you assembled the keyboard and thus the contacts may not be made after such an assembly.

(*) I mean AFAIR because I opened the ES8 a second time later to replace most contact strips, hoping that would solve the damned clicks for good. It solved... for a few weeks, after which they returned in all their glory.
Looks like the middle rubber strip isn't sitting flush in the front. It's very important before screwing down circuit board strip. The rubber strip should fit in a slot or some use nipples that you push through small holes to hold it down firmly. Good luck MooganDavid
Thank you guys ! I had to bring someone to repair it for me because I was too affraid doing something I shouldn't, so basically his work resumed at cleaning the silicon thing with alcohol and dry it and it worked... and also the problem has dissapeared
Very good (and lucky) !!!
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