2015-12-07

Repairing Korg Krome's blank screen

I'm posting this here in hope that it helps other people facing the same issue.

This week-end, my Korg Krome synth's display became blank again. Given that it's a touch device, it becomes pretty useless once the display doesn't work anymore. It's not the first time it happens, I even disassembled it once hoping it was only a cable or solder issue, but it worked again after being reassembled for no apparent reason. I noticed that often after it failed, it would re-appear after a few hours/days, and sometimes it would disappear again. I thought the LCD was dead. I ordered a new one on the net (almost any 7" 50-pin LCD with a resolution of 800x480 and about 15cm of cable will work). It cost me $15, it worked and failed again after one week. 

Finally I disassembled the Krome again and observed the LCD power board, and found that the LCD reset pin (44) had a strange voltage of 1.5V instead of 3.3V. The reason is a design error in the choice of resistor R28. It's 10K while it should be around 1K. With 10K it doesn't have enough strength to completely release the reset and it depends on the LCD's tolerance (which probably changes with aging). 

I simply soldered a 1K resistor on top of it, verified that the voltage on the reset pin is now 3.3V, and the problem is now fixed. 

In order to fix it, one must proceed like this : 

1) put the Krome top-down on a soft surface like a bed. Take care of not putting too much strength on the joystick 

2) remove all screws on the back. There are a lot, something like 37. Important : there's no hidden screw, so it's not needed to remove the rubber feet. 

3) gently pull the back vertically, it will very easily come. If it doesn't, you forgot a screw. 

4) you'll see the mainboard at the center, close to the back where the SD card is. You'll have to remove the screw with the plastic washer, and gently pull the soft plastified tin foil which protects against radio emissions I guess. 

5) then remove all cables going to the motherboard (no risk to confuse them later, though it's better to take a photo). In order to remove the flat ribbon at the bottom, you first need to pull the brown part of the connector outwards to unlock it (do not force, it will come by alternatively pulling each extremity with your nail). 

6) remove the 6 screws from the motherboard, then take the motherboard out of the system. 

7) remove the metal frame that supported the motherboard. 6 screws again IIRC. 

8) you now see the small board with its cables like in this photo :

LCD controller board
It is not strictly necessary to remove the board to fix it but it's better as static electricity could destroy the LCD. The large flat cable at the top goes to the LCD. The small one on the top right is for the touch pad. The other small one at the bottom right goes to the audio board on the right. In order to remove the LCD cable, you first need to pull the white part of the connector upwards to unlock it (do not force, it will come by pulling with your nail). The other ones need to be pulled in their own direction without bending them. 

9) remove the 2 screws holding the board, and slightly unscrew the 4 other ones holding the metal frame so that you can get about 2-3 mm of clearance. That will be enough to release the board from the 2 plastic tips which hold it. 

10) find the resistor on the board. It's called R28 and marked "103" (10*10^3 ohms = 10K). There are two such resistors at the bottom left of the "CN17A" marking. The upper one is R29 and doesn't need to be touched. The bottom one is your friend. These two photos help locate it better, click on them to zoom in : 
Resistor R28 and marking
Zoom on R28 and LCD pin 44
11) DO NOT REMOVE IT! It's a small component, if you're not at ease with soldering small components, you'll certainly destroy the board by pulling off a copper lane. Instead, just find a 1 to 2k resistor on another unused board such as a dead motherboard. Such a resistor is marked 102 to 222. Note that the first two digits are less important than the 3rd one which is critical (exponent). It MUST in fact exactly be "10" to "22" followed by a "2". If you have something smaller than a 2 on the last digit, reset will never work. If you have something larger, your fix is useless. 

12) Once you've found this new resistor, directly solder it on top of R28. If you're having trouble soldering something that small, first stick it on top of the other one using some superglue then put a very small drop of solder on each side and that will be all. You must not heat it more than 1 or 2 seconds per side. The amount of tin to add is around 1mm * 1mm only. 

13) verify with an ohm-meter that you have slightly below 1-2k when you measure across the previous 10k resistor. If so you did it fine. 

Edit 2021-08-28: 13bis) see blow, the C69 capacitor is likely bad!

14) reinstall the board, then tighten the metal frame's screws, screw the board, reconnect all connectors (be careful with the small ones, you don't want to bend them or they could cut). Then pass the motherboard wires that you might have moved close to the board, reinstall the top metal frame, then the motherboard, reconnect all wires and power on. It must work. Once it's OK, you can finish to reassemble everything. 

I noticed that black screws are used outside and grey ones are used inside, except a few holding the LCD frame and the keybed which are also black. 

Try not to mark your screws. A screwdriver made for PC parts is perfect and will not mark. Count around 10-15 minutes just to disassemble everything, about as much to reassemble, and as much to fix the board once you have found a suitable resistor. 

If you don't have a resistor, you can find one at an electronics components shop. Just go there with your board and they'll find the proper size. I guess it's a "0603" type of resistor (it indicates the size) though I'm not certain and forgot to measure. 

I forgot to say, I noticed that the original Krome's LCD is of very good quality. When you replace it with a cheap one, images are really ugly. But that was better than nothing. 

Hoping this helps other people! I've read on various forums that many other people got in trouble with the same issue and it's too bad that some repair shops take them hundreds of bucks to fix this. So do not hesitate to spread the message and to share your experience.

Edit 2021-08-28
 
A commenter below mentioned that he figured that the C69 capacitor was bad and read as a resistor. That's not common for SMD capacitors, but since my Krome turned bad again, it was time to open it one more time and test.



The C69 capacitor is circled in red above, and the R28 resistor in yellow. At first I tested it with an ohmmeter and it read as a resistor but that's common when devices are soldered as the current may flow through other components. I desoldered it and tested it:
 


Verdict: 252 ohms! It should read infinite. This capacitor is abnormally dead! It definitely indicates a low quality one, likely caused by a poor choice of vendor, which would explain why Korg seems to remain silent on this problem that affects plenty of users.

And thinking about it, it totally explains the aging and the need to replace the resistor to compensate for the capacitor's own resistance!

I replaced it with another one i had, of about 4 uF, but this value is not very important, and I think that even 0.1uF will work. I believe the size code is 0804. I verified that even once mounted it reads infinite, so this is a good test to perform before desoldering it. If it reads less than a few tens of kiloohms, it's dead and needs to be replaced.

I was so convinced it would work, I reassembled everything without prior testing. I repaired it so many times now that some screws are freewheeling, but the nice point of opening it often is that it now takes me less than 5min to reassemble it :-)  I plugged all cables and turned it on. And guess what ?
 

So big thumbs up to @unknown below in the comments section for figuring that one! To those for whom it still does not work when changing only the resistor, try to change this capacitor! Becareful not to pull a track, though!

86 comments:

  1. Mr Tarreau, THANK YOU THANK YOU for posting this material! We have a Korg Krome, and the screen has been out for months. I was researching ordering one, and then found your post. We did it (with a regular 1K resistor) AND IT WORKS! Thanks again!

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    1. You're welcome. I'm really glad this post was useful. I know the frustration you've gone through with this device not being controllable anymore. By the way mine still works pretty well one year after the fix.

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  2. Hi does it retain the original screen or is it replaced?

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    1. Yes I kept the original screen as it's of much better quality than the replacement part I ordered.

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    2. I need new display touch screen. Can I replace my original display

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    3. Yes you can. As I mentioned, I tried another one found on eBay for around $40 and it worked. However the quality was much less good but it made it very usable. Be very careful about the dimensions, you may have to disassemble the one you buy to make it fit into the existing one's metal frame. It's not easy to do but nothing very complicated either. Just requires patience.

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  3. Hi Mr Tarreau. I know that this post is old but i was just wondering if you don't have any experience with the Korg Krome touch screen. My screen didn't respond to any touch. So i did buy new one from Korg and i did replace it today. But the new screen is not working ether. So i am guessing that could be some different issue. Do you have any suggestion? I did try the calibration but since the screen don't respond any touch i couldn't do it. Thank you. Pavel

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  4. Unfortunately I don't have any suggestion. It may be possible that the touch panel connector is damaged or is attached to a cut copper lane. It's the "TP" connector at the top, you may want to follow the lanes to try to spot any defect. Otherwise I'm afraid you may have to change this board and it might be expensive despite being almost empty :-/

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  5. Hi, Mr Tarreau,
    I seem to be experiencing the same issue. As I am a novice to circuit boards I thought it might be a good idea to get another board before attempting the surgery. Then I have at least one circuit board in one piece. My problem is finding the part number of said board. Would you know this, or where I can locate it before pulling the Krome 88 apart?

    Many thanks in advance

    Andy Partington

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    1. Unfortunately I don't know. There is little risk if you're cautious. The most important you need is a fine soldering iron. If you use a large one as found in many shops, you will damage the board.

      If you don't feel easy with soldering, there's an alternative. You can use a bold pencil (2B/3B) and "draw" on the existing resistor until you can't read the value anymore. It will deposit some graphite and will lower its resistance. This may work for some time.

      Otherwise you can probably find a friend around you, more at ease with a soldering willing to help you on it. It's a very simple task which takes only one minute for trained people. The boring part really is to open the cover, but you can do it before he comes ;-)

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  6. Thank you, Sir, and thank you for the extremely fast response. The use of a pencil seems quite a novelty, will give that a go for starters. Thanks again, have a great day.

    Andy

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  7. Hi Willy my name is luis and i am an italianna wanna be musician(my real job is security officer)and hava problem with the touch pad of my korg krome....the display is black with a yellow strip on the left side...if I touch it i can hear the response with the standard beep or buzz....do you think it is the same problem that you experienced?thanks for your kind response .luis

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    1. Hi Luis,

      oh yes, it definitely sounds very familiar. I feel sorry for you, but at least you know there's a workaround now :-)

      Don't be afraid by the operation, it's long but not very difficult if you take your time. Also take some photos while doing it. If you don't have a resistor to place on top of the existing one, you can try the pencil trick, it'll just be harder to know when you've put enough of it.

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  8. Thanks Willy for your quick response,one of my best friends is an electronic guru so I will bring my krome to his laboratory......i wish to you a very happy new year....ciaoooo

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  9. You are the best brother..all i can say is Godbless you and thank you so much...you have a good heart thank you for sharing this knolege 😊🙏

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  10. That is indeed the problem with the Krome's screen. Thank you very much for sharing your experience. I am very grateful to you for helping to solve problems.

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  11. Hi willy ..you site is awesome thank you in advance for advise on an issue I have . I have korg krome 88 that the LCD screen is cracked and is only responsive on upper left hand corner . Can I just replace the glass or do I need to replace the whole display?

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  12. I don't know in your case, however the LCD, the touch sensitive part and the front glass are 3 separable parts. If the glass is cracked only, maybe you can replace just it. If the LCD itself is cracked you'll have to replace it. But if it's not responsive it seems to indicate the touch part is broken as well so you may need to replace the full LCD assembly. There might be some for sale on the net, I have not searched. Note that fitting other components into the metal enclosure is not trivial, because you never get an exact size replacement part.

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  13. Hi Willy I have a doubt; so the resistance can be for example a 102, 182, 202, 112, 212, 222, 142, etc... as long as the last digit is a 2 and the first 2 remain between 10 and 22, we are good to go right?

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  14. Yes, you understood right. If the first one is above 22, it might still work, but the further you'll go, the the more you will rely on luck. But if you have nothing else but 332, you can try anyway. You can place two of them in parallel as well. The resulting value will be 1/(1/A+1/B) where A and B are the first two digits. For example if you have only one 332 and one 472, placing them in parallel will give you 1/(1/33+1/47) = 1.9k ("192"). It's just that it's not easy to stack 2 resistors on top of another one.

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  15. Muchas gracias por tan importante data.tuve el problema de la pantalla.reemplaze la r 28 y arrancó.muchas gracias

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  16. If its a design error in the resistor selection from the manufacturer then how it was able to function fine before the problem arised.

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    1. It's explained in the text, mainly due to components tolerance which tends to fade away with aging. This also explains why it was probably not noticed during the design phase nor during post-production QA. Anyway 4 years later mine is sill OK and I received other comments from others having successfully fixed theirs so that's great. I just don't know if new ones sold right now are fixed.

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  17. I think I have the same issue. My keyboard boots up normally. I hear all sounds. I am certain infact that the touch on display is working fine caise i hear that beep sound while you hear when touching the screen. I see nothing except a thin vertical yellow line on right side. I stay in a very remote location with no service centre within 500kms radius. Please comfirm if following your instructions would help me solve the issue. I have attached few pictures.

    Please help!!

    https://drive.google.com/file/d/1dmCeGW95yPG-IzPLmBhyKWcRcjr2M6KM/view?usp=drivesdk

    https://drive.google.com/file/d/1dmVVzqEWWvvIcvdeZaDhQbY5sFjMeLhG/view?usp=drivesdk

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  18. It indeed looks extremely similar. Mine also did things like this. If you're not too impatient to use it, you can also unplug it and wait for a week before turning it back on. For mine it used to work quite often this way. But frankly the operation is doable. If you don't have a source for components, you can try to use a pencil and put a lot of graphite on the resistor. Or you may order a barely conductive pen and draw on it. But there are quite a lot of chances that you can find such a resistor in an old device you don't use anymore.

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    1. You assuring me is enough. I am going to try this stunt on a Sunday.

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  19. hi Willy may I know how many pins is the white flat cable that seems to be the problem on my krome.

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    1. It's a 50 pin cable. Fairly common cable in fact, you'll find tons of 50-pin flat panel displays compatible with it.

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    2. thank you Sir, will buy it today, i have thesame issue on my krome and i havent used it for months because of that. i bought a used but good lcd board, but that white FFC cable seems to be damaged.

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  20. /Trying to respond for the third time after losing my comment twice on this shitty blogger interface which keeps logging me in and out in loops!/

    I said, you don't need to change your LCD, only to change the resistor if you're facing the same problem as me above. I initially bought another LCD but that was not the problem. Once I fixed the resistor, the original LCD worked pretty well (and still does 4 years later).

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  21. Thank you so much for the post Mr. Willy. I am facing with krome 61 - while booting there is a dim backlight in display. After that it went off. Though we can operate with touch panel voices, unable to see the display

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  22. Dear Willy, how are you? I'm Gustavo Moyano, engineer in electronics from Argentina.

    I made this change one year ago, and it was OK. But now, the same problem appears....blank screen again. Would you help me? Any suggestion?

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  23. Hey Gustavo, guess what ? Mine died again 6 months ago. I finally replaced it with the cheap one I bought, and today it failed once during operation, suddenly it turned white with moving lines. I've restarted it. There's a serious engineering issue on this synth, it pisses me off! I'm seriously considering adding an external reset switch, I'm fed up. They should make an expander from this synth so that we can benefit from the sound without being forced to deal with the broken screen and awful keyboard!

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    1. Hi Willy, thank you very much for your reply!I'm Sorry, but recently I sent you again the same question because I was not sure if you had received it. Anyway......the problem here is that it is impossible to get spare parts....I'm thinking to reduce the value of R28 to 500ohms....what do you think? any other idea? Thanks again for your prompt reply!! Have a nice weekend

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    2. No pb for the second message. It was apparently waiting in moderation box. Regarding the 500 ohm resistor (likely 510) I think it can be too small, but you can try. I was rather thinking about replacing the resistor and capacitor with a 3-pin reset chip such as https://www.onsemi.com/pub/Collateral/MAX803-D.PDF or https://www.ti.com/lit/ds/sbvs158a/sbvs158a.pdf to get something reliable. I think we don't care too much about the time it takes to reset the display because it's initialized very late in the boot process, it takes more than one second to give any feedback so even a slow chip sending a 200ms pulse will be fine. But quite frankly, having an external reset button to be held during power up seems like the most reliable solution to me.

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    3. Hello Willy, I got a solution. I disconected the blue led only for aesthetics purposes and.....display works again!. It seems that there is a problem with supply system. BR - GM

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    4. It should not be related. However I noticed several times that disassembling it would solve the problem for a while, just as if a capacitor wouldn't completely discharge and prevent something from reinitializing. This just makes me realize that the power supply is always on since it uses a momentary push button. I'm going to disconnect mine right now to see if anything changes next time I plug it.

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  24. Thank you so much for posting this!! This was the fix I was looking for.

    Bob O.
    Resurrection Electronics

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  25. Works excellent for me!! Just remolace the 10k resistor for a 1k.Thank you so much!

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    1. Cool, I'm really happy. Just for your information, mine worked about 2 years with this fix and started to fail again. I was fed up, I replaced the display and it went OK for some time, then started again to fail 2 months ago or so. I'm suspecting there's something very wrong in the reset circuit there. Or maybe it's the power supply delivered to the display that is not stable enough anymore. I'm too fed up with it, now I'm setting the programs using the keys. I'd rather have an expander made with the same techno, the piano and drums sound really good but the build quality is so cheap... Never going to by KORG anymore.

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  26. Hi
    I replaced the R28 and then the LCD.... but the screen still does not switch on. I can hear the "bip" when I touch it, but nothing more...
    Maybe one of you get an idea. The problem could be the screen controller booard ? where could I find one ?

    Best,
    Emmanuel

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    1. Unfortunately at this point I have no idea :-( Mine turned white a while back as well and I'm fed up with opening it. Korg has been totally silent on this problem which affects many of their customers, it's unacceptable. Just for this reason I think I will never ever buy any product from such a dishonest vendor!

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  27. Thank you for the detailed notes and images. They have has just enabled me to fix my Krome. I am an elec eng by training and original career (not these days), so wasn't phased by the prospect. But I have never before tried to fix such a tiny SM component. Having to buy 100 1k resistors just to use one is a bit strange too, but still cost me less than £2! I didn't trust my hand soldering something so tiny, so I used good quality conductive paint/glue on each end instead and it worked fine. Many thanks, again. Martin A.

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    1. Cool, glad it worked for you. You shouldn't be afraid of small components, unless you're using a big soldering iron. But with a fine tip and patience it's possible to do impressive thing, as you can see here with 0.5mm-wide resistors and capacitors: https://wtarreau.blogspot.com/2020/09/breadbee-build-your-own-single-board.html

      Regarding the number of resistors, it's possible to find them by 10 or 20 on ebay/aliexpress, but this won't change the price as shipping is more expensive than the components. What I like to do instead is to buy various common values so that I have stock for another project :-)

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  28. спасибо за помошь у меня точно такая проблема и я думаю что поможет

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    1. Good luck! Please post in English next time, though :-)

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  29. hi ... I have an idea to draw with a pencil and a little glue on top, do you think glue will not spoil anything ??????

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  30. I really don't know, it's a matter of resistance. If it's not enough it will fail, if it's too much it will fail as well. You could maybe try with a conductive pencil, these are used for electronic repairs. Once dried, you'd scratch most of it to leave only a very thin strand, probably that this could work.

    Another possibility is to buy a cheap thin soldering iron at a DIY store, and buy whatever cheap electronic device you can find in a box of $1 China-made crap that will serve you as a source of components. Devices made for analogic stuff have more chances of containing components (e.g. a cheap radio or MP3 player). Then you can train yourself on the board itself until you feel ready to attack the synth!

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  31. what is the size of this resistor in mm?

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  32. thanks, I will look for such a resistor

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    1. Is it possible to sing an ordinary 1kΩ resistor ???

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    2. Of course, as long as you're able to solder it on top of the other one. I've done this plenty of times in other contexts. Be careful about the surrounding metal frame so that none of the resistor's pins touches it!

      PS: no need to send the same message multiple times, as you're not authenticated, Blogger puts your comments into the moderation queue, waiting for me to unblock them, that's why you don't see them after clicking :-)

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  33. Thank you Mr. Willy for helping me fight korg

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  34. Change C69 too, I had changed R28 and works good for 2 months.. I test that voltage was 0.81V without connect the display.. and I found that C69 is in series with R28.. and read like a Resistor too, I´m put a 10uF smd cap, taking as reference C96 which is in a similar circuit. I don't know if it is the correct value, but it works, now I have 3,25V

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  35. Interesting! I think it's not in series but connected to GND while R28 is to 3V3. But your observation totally makes sense. It could be that the problem is entirely with this capacitor which shows a resistance while it should not, and would explain the need to change the resistor.

    I'll try on mine, as it's failing again.

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    1. Thanks! Willy, I´m Mr Unknown in the previous comment. I really appreciate that my suggestion has worked. Your blog is my first consultation whenever I have a question. Now I am working with another Krome that directly does not turn on. Best regards from Argentina. Diego

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    2. Hey @AmreinFX, you're welcome, many thanks for your trick, my Krome also continues to work flawlessly one year later, and you found the real cause. Kudos for this!

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  36. Hello Mr. Tarreau, I tried to fix described problem with Korg Krome Display according to Your description, but it was not successful. The problem is very well seen on YouTube video:
    https://www.youtube.com/watch?v=O1AtHDpqhgc
    Please do You have some idea?
    Or - service manual (wiring diagram) for Korg Krome?
    Thank a lot for Your help
    Jan Skrobacek
    jan.skrobacek@gmail.com

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  37. Hello Mr. Tarreau, I tried to fix described problem with Korg Krome Display according to Your description, but it was not successful. The problem is very well seen on YouTube video:
    https://www.youtube.com/watch?v=O1AtHDpqhgc
    Please do You have some idea?
    Or - service manual (wiring diagram) for Korg Krome?
    Thank a lot for Your help
    Jan Skrobacek
    jan.skrobacek@gmail.com

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  38. The commenter above suggests that the responsible might be the capacitor C69 that is close to the resistor and that has abnormally aged, showing a resistance while it should not. Actually that would make a lot of sense, even if that's quite uncommon for SMD capacitors. I haven't reopened mine yet, but next thing I will try will definitely be this. If yours is still opened, you should probably try to replace this capacitor. I was thinking about drilling a hole on the rear and installing a push button for the reset because I'm really really fed up with this crap :-/

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  39. Confirmed here, 252 ohms on mine. Replaced and booted fine again! Kudos for figuring this one and thanks for sharing. I've updated the article to mention this. Let me know if you'd prefer me to mention your real name there (if so, please indicate it to me). Thanks!

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  40. :-) bad c69, the same type can be bad even in other places. petr pacal, CZ

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  41. Hi! I'm having a seemingly unsolvable problem related to this. Nobody knows what solution i might have. My problem is the screen works just fine, but the touch panel works partially. Sometimes it would work just fine, and then when pressing anywhere on the screen, it would activate different parameters on other places in the screen. For example, pressing the Category button would start recording or activate the drop down menu. Can't navigateo r change anything at all. If anyone could guide me to what it is i should do, i would appreciate it. I have no means of buying another one. Thank you very much!

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  42. This sounds like a defective touch sensor. It's a resistive one, so if it got pinched somewhere it can possibly start to react incorrectly. It's also possible that some dust got stuck up between the plastic cover and the touch film on one edge. Maybe try to pass a paper foil under each edge to be sure. And inspect the touch film to be certain it's not damaged. If it is, you will have to change it and to recalibrate it.

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  43. Hello.what is the resistor assembly 47 ohm in the board?0402 or 0603 size?thak you for replying

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    1. Just checking on the photo, it looks as large as the capacitor is wide, so I would think a 0402 then. Honestly it will not make a big difference. Also in doubt prefer a smaller one than a larger one. The larger one may be difficult to solder while the smaller one can touch both ends by applying a little bit extra solder.

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    2. In the AliExpress 0402 and 0603,I don't know what is size in the mother board

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    3. I understood, and that's why I'm suggesting that in any case you should use 0402 because even if it's not this one it can be adapted. You cannot shorten a larger one to make it touch terminals. So better use the smaller 0402.

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  44. hello my synthesizer worked for 2 months after the resistor was re-soldered and died again. Now the screen does not turn on, although it used to turn on for an hour and a half and din. read the corrections with the capacitor and do not know if it will help? I already soldered resistor 103 in place as in the original and nothing. If it's not difficult, please help

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    1. I can confirm that the capacitor fixed it for me and mine still works 3 months later. It was the defective capacitor that was acting like a resistor against the original one, forcing us to replace it to compensate, until the capacitor became even worse. Just change this capacitor and you'll be OK. Usually it's less easy to measure capacitors, not all multimeters support them. I suggest that you pick one that's installed closed to a large integrated circuit on a board, such as a RAM or microcontroller, usually they are decoupling capacitors and the right value for this (i.e. 0.1uF). If you have an old unused DIMM stick, you might find one on it.

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  45. Original doesn't fit? did not understand? do I have to put another one?

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    1. That's not what I'm saying. Contrary to the resistor where you can install another one on top, you have to remove the capacitor because it's partially shorted, an install a fresh new one. It's more difficult to chose a capacitor if you're not in electronics because usually there is no marking on them. That's why I explained how to select one to steal from another board.

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  46. Thank you friend!!! I re-soldered the capacitor and everything works.

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    1. Awesome! I'm wondering how many Krome we've saved from the beginning :-)

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  47. Я думаю что проблема не у всех.... Видимо была определенная партия синтезаторов с этой поломкой....вот и все дела. Жаль что техническая поддержка korg это утаила

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    1. Translated to English: "I think that not everyone has a problem .... Apparently there was a certain batch of synthesizers with this breakdown .... that's all. It's a pity that korg technical support hid it"

      Yeah I agree. I guess they ordered low-quality capacitors like everyone else in the early 2010s and never wanted to admit it because they were afraid to recall many devices.

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  48. Да!!! Подумайте??? Как отозвать 19990 инструментов??? Легче скрыть эту проблему

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    1. Please, post in English only. Translation here: "Yes!!! Think ??? How to recall 19990 instruments ??? It's easier to hide this problem".

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  49. Hi willy
    I have a small question, when the screen is black, does the krome still producing any sound, can you still using with the buttons or it appears dead? I'm asking that because I have seen an offer for a 88 black issue screen which is sold for spares...

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    1. It works perfectly (except for the screen). I could even tap on the screen on previous traces of my fingertips which did correspond to the instrument selection at the top and to the "next" button at the bottom, to select the one I wanted. Similarly, pressing the buttons to directly enter an instrument number did work fine (I printed the whole list for this). If you can buy a 88 keys for a cheap price and it's its only issue, that would be nice. But I doubt someone would sell it for spares only for the screen, since it can still serve as quite a good piano on the default setting.

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    2. So the issue might be diffrent because the guy said there is no sound and no screen ...maybe the power supply...

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    3. Very possible, but in this case if I were you I wouldn't try my luck (unless it's extremely inexpensive). Their power supply is not among the simplest from what I remember about the inside, I seem to remember it has multiple voltage outputs, and maybe a separate, likely independent one for the audio output stage. So it shouldn't be as simple as replacing it with the first 12V PSU board around.

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