I just noticed that all the lights are on — for example, the ones that indicate which knob function is selected or which tracks are selected for control with the faders.

Thanks again.

Test Mode - use C#2 major chord while powering up.

Per the service manual - https://www.manualslib.com/manual/3198308/Yamaha-Modx6.html?page=37&term=mode&selected=3#manual

There could be a loose or broken connection inside, water damage or an accumulation of dirt.

If the tests don't show anything and you don't hear anything loose when light shaking you will need to either open it up yourself or take it to a service center.

What's local control set to?

[UTILITY] button, "Settings" -> "MIDI I/O" menu.  If it's off, turn it on.

When local control is off, the keyboard expects it will get MIDI messages from an outside source.  Many times it's the messages coming from MODX to begin with that are echoed back to MODX through the DAW.  If you don't have anything echoing the MIDI back then it will seem like nothing is happening.  Although the keyboard is sending MIDI out when you turn knobs and press keys 

Posted by: Toby

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Test Mode - use C#2 major chord while powering up.

Per the service manual - https://www.manualslib.com/manual/3198308/Yamaha-Modx6.html?page=37&term=mode&selected=3#manual

There could be a loose or broken connection inside, water damage or an accumulation of dirt.

If the tests don't show anything and you don't hear anything loose when light shaking you will need to either open it up yourself or take it to a service center.

 

Hello.

First of all, thank you.

I did it and reached the Test Mode screen. But as none of the buttons work, I was not able to do the test. 

The problem with the service center is that I have not a service center near. I called the nearest one, but they don't want to give me a estimation of the reparation in the worst case... 

I don't dare to open the keyboard, so I will use it with the screen, which works properly (but not so nimbly).

Posted by: Jason

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What's local control set to?

 

[UTILITY] button, "Settings" -> "MIDI I/O" menu.  If it's off, turn it on.

 When local control is off, the keyboard expects it will get MIDI messages from an outside source.  Many times it's the messages coming from MODX to begin with that are echoed back to MODX through the DAW.  If you don't have anything echoing the MIDI back then it will seem like nothing is happening.  Although the keyboard is sending MIDI out when you turn knobs and press keys 

The keys work properly, the screen too, the faders and the knobs too... It's a problem with (all) the buttons. 

I asked here just in case someone could give me another way to try, and Toby give me it, and it confirms that something is broken... so thanks both of you for your help.

@Jason ask what local control is set to but your reply didn't say.

I did it and reached the Test Mode screen. But as none of the buttons work, I was not able to do the test. 

Too bad - on some models you have to press a button in order to get going. Other models you can use the data dial.

The problem with the service center is that I have not a service center near. I called the nearest one, but they don't want to give me a estimation of the reparation in the worst case... 

Unfortunately that could also mean they just don't want to bother with it. It's obvious someone can't provide a 'worst case' estimate without doing an exam but, at a minimum, they should be able to give you a basic cost to:

1. open it up

2. check for anything obviously wrong

3. close it up and return it to you

There are one, or more, button boards in that model that are connected to the main board by a ribbon cable. That cable can easily come loose if the normal coarse of moving the instrument or, worse, if it was dropped slightly and jarred.

Those 'obvious' things to check would be loose or disconnected cables as well as observing, with the case open, what happens when they press one/several of those buttons that don't work. They may see the button board flexing or moving indicating it is no longer secure. If you press a button on a loose board and the board moves under the pressure it may be the button hasn't depressed at all giving the illusion that it isn't working.

A reputable shop should have a base/minimum 'take a look see' rate but based on that shop's response you might be better off talking to a different service center. Since you said you don't have one near you it won't really take much longer to ship to one further away.

I don't dare to open the keyboard, so I will use it with the screen, which works properly (but not so nimbly).

Don't do it if it is on warranty or if you aren't comfortable doing it. But the process for just opening it up is pretty basic and there isn't much chance you could do any damage as long as you do the basic protection against static discharge.

Since your issue is with 'all' the buttons odds are good it is a loose button board or cable. You could try an OS update if you aren't on the current version but I wouldn't expect that to resolve the issue. And with no buttons available you may not even be able to do an update.

Buttons are on an I2C bus.  I haven't looked at the schematic to see if there is interconnect likely to be a source of failure.  For me, in the past, I've seen solder joints at the I2C master controller cause this sort of failure.  In fact, I have a MO6 that's been sitting with its guts removed waiting for me to (re)diagnose and probably touch up the rework that's already been done years ago.  It's worth finding a local keyboard technician and have them take a look.  You can either look through the list provided by Yamaha that covers the warranty centers or, if not under warranty and not happy with the options from the list, go outside of this and ask around or look up who's best to take this on.

@Jason ask what local control is set to but your reply didn't say.

It is in "on". I tried it also in off, just in case.

Don't do it if it is on warranty or if you aren't comfortable doing it. But the process for just opening it up is pretty basic and there isn't much chance you could do any damage as long as you do the basic protection against static discharge.

Since your issue is with 'all' the buttons odds are good it is a loose button board or cable. You could try an OS update if you aren't on the current version but I wouldn't expect that to resolve the issue. And with no buttons available you may not even be able to do an update.

It is out of warranty and the only thing I have opened is a computer... but maybe I try it (firstly I'm looking for videos).

The strangest thing is that all the button lights are on. Can a loose button cause all the lights turn on and stop working?

I have already tried to update it, but it is impossible to do it without the buttons.

Thanks again.

Buttons are on an I2C bus.  I haven't looked at the schematic to see if there is interconnect likely to be a source of failure.  For me, in the past, I've seen solder joints at the I2C master controller cause this sort of failure.  In fact, I have a MO6 that's been sitting with its guts removed waiting for me to (re)diagnose and probably touch up the rework that's already been done years ago.  It's worth finding a local keyboard technician and have them take a look.  You can either look through the list provided by Yamaha that covers the warranty centers or, if not under warranty and not happy with the options from the list, go outside of this and ask around or look up who's best to take this on.

Thank you.

You don't seem prepared to do this on your own.  Few are.  Please do have it checked out by someone who will either not further damage the keyboard or make it right when they do (i.e. carry an insurance policy that covers the unlikely event something goes wrong).  

Even if cracking it open there's a right and wrong way.  If you're unaware of the what this means, please do put it in the hands of someone who knows how to control ESD and properly service the instrument.

Of course you always have the option of selling it as-is at a loss vs. new but use the funds to invest in a newer model.  Someone who knows how to repair this would be fine with paying under market used prices and you may ultimately benefit vs. the repair costs.  If the keyboard is otherwise in good condition, $900USD seems like a good starting point.  It's taking the general used price and taking 25% off for as-is.  Lots of options.  You can still backup the instrument using just the touchscreen I believe.  Haven't tried this if the utility menu needs physical buttons or not.  Unless you already have a recent backup and don't need to worry about this.

You have limited options.

The strangest thing is that all the button lights are on. Can a loose button cause all the lights turn on and stop working?

A loose board, board connection or cable connection can cause all kinds of things. Electrical circuits need a 'circuit' - meaning both a power and a ground. If the circuit is broken (bad connection, stuck component) bad things happen.

I have already tried to update it, but it is impossible to do it without the buttons.

Everyone is just trying to give you the best info available and NOT trying to talk you into taking any particular path.

Based ONLY on the info you have provided these would seem to be the three most salient facts:

1. the instrument is NOT useable in the condition it is in

2. the instrument MUST BE opened for anyone, you or a service tech, to visually inspect it for possible damage or problems

3. you do NOT likely have the tools, nor the experience, to remedy anything other than a loose board or cable connection

@Jason pretty much summed up the options available to you.