YamahaDGX-220 YPG-225 Keyboard one year old. Turned it on and it does not play the scale. You play middle c then it sounds like you get two off sound d and so on. Was fine when I shut it off. No storms around and kept in an air conditioned room.When you first turn it on Yamaha comes on at once it does not roll across screen.

You can use the guide for troubleshooting the YPG-225 provided by ifixit here. There is a section labeled "Keys don't produce sound". If you need the manual for this keyboard, it is here.
If those keys which do not produce a sound are somehow hanging (are lower than the other keys) and are somehow slack, the problem is related to broken keys. They need to be replaced. In this case, you can use this guide here on ifixit.

Just a shot in the dark but a lot of keyboards allow for splitting the keyboard in half or even in quarters to assign multiple sounds... have you tried a total reset? Or explore the manual for setting up a split keyboard. Might help.

For the best info contact Yamaha support. Here's the link-

Digital Pianos Keyboards Guitars Drums Live Sound and Music Production...

I had the exact problem, mine was a YPG 535 brand new in box I put everything together with stand and FC4 pedal. When i got ready to play just a blue screen and none of the red lights came on and no sound, I notice when i was messing with the on and standby button hopeing it would work the speakers would make a popping noise I personly thought it was a manufacturing defect.....i'm sending it back to have it replace. I never had problems with yamaha products but seems like more and more defects are happing with newer portable grand series!

Call Yamaha at 714-522-9000 and ask for a tech who works in your area. Attempting self repair could void any garuntee that is covering the problem.

Call Yamaha at 714-522-9000 to find local dristubators/ liscend yamaha dealers. You may also visit the yamaha website.

That's very annoying! The keys press on to a contact strip running the length of the keyboard. Over time this wears out and notes can either stop being dynamic or stop playing altogether. You can buy the strip off ebay and have a go replacing it yourself - not too expensive. I paid someone 50pounds to supply and fit one to a 61-note keyboard.

#0031 DGX-630/YPG-635

Hi here is the manual of your Yamaha

techbelkin

You need to use a transformer type voltage convertor.

DO NOT use the type for converting 220 down to 120 for hair driers.

The voltage should NOT be a problem as usually these will operate down to 100 volts. If the keyboard is sounding correctely, that would indicate there is NOT a problem with voltage.

It is LIKELY that the connections to the LCD were damaged in shipping. There are many, many connections to the glass assembly and if dislodged will have lines across the display.

Repairing this is usually not something one can do unless very experience in electronics.

If you know how to use a multimeter then I suggest you measure the voltage from your wall adapter plug that you plug into the keyboard. If that has approx. 9Vdc, then take a look at d151 on the power supply board. See if it is passing voltage. Voltage should pass only 1 way. If you have voltage on one side but not the other then the diode it is open and needs replaced. You can find the diode designator on the board next to the diode.