- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
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!
I had similar problem with my DGX620. In my case the display sometimes got blue and sometimes worked fine. The cause was a bad contact of the display flat cable.
I opened the DGX620 and then I cut a small piece of plastic film (35mm negative) with exactly the same width of the flat, disconnect the flat cable and then reconnected it using the film on the other side (non contact side) to increase the pressure and guarantee a good contact. No more problems from nov-2012 till now.
Check if the display has a contrast control. When these get turned down, the display is blank. Sometimes they are a littel shaft coming out of the case, other times it is a setting in a menu... how they expect you to see the display to set it in these cases is beyond me...
Open the unit and see if it has a battery that holds the settings. Check the voltage... it should be around 3 volts. If less than 2.5 volts replace it.
Verify the INTERNAL regulated power supply as the external you verified with new unit. The external is likely regulated within the D4 and either due to an overload or bad regulator may be below the voltage to run the processor. It is likely 5 volts and anything over 4.85 would be acceptable.
If you get absolutely no sound, not even a pop when changing the standby switch, this probably means the rectifier OR the switch has failed. The red light just means power is getting to the power transformer... probably fuse is OK.