My Yamaha WX5 D# key sometimes has no response it keeps play E note, but sometimes it works, is it setting problem or defect ?

SOURCE: Yamaha Electronic Piano- certain notes malfunctioning

Either the first or second closure matrix line for the "A" keys is bad.

This may be a cracked or shorted circuit board.

A bank of diodes is used to prevent sneak electrical path if more than one octave has notes pressed.

First thing is to clean ALL the key contact areas and the conductive rubber pills with 99% isoprophyl alcohol.

This involves dis-assembly of the key area. If you are not competent in electronics, best left to a pro shop.

The keys are scanned in a matrix, two contacts per key and all the individual notes are in common (all the "A;s", "B's"...) And each octave is strobed for the first set of contacts and then for the second set of contacts. an the whole octave is read in parallel.

The reason for two contacts is one closes first and then the other as a key is lowered. The time between these is measured and is the note VELOCITY which for a piano controls the loadness of the note. IF ONE of the two fail, the loudness will vary as yours does.

SOURCE: bp's problem. I have a CLP-110, Yamaha

call up Yamaha. They will fix it for free as it is a manufacturing fault.

Testimonial: "Thank you very much for that timely information. I'll call Yamaha today and see how they want to proceed. Thanks again."

SOURCE: I can't get my Yamaha

Reread your manual pages 14 and 15. Note page 14 tells you that "When using a monophonic tone generator such as the VL70m, the Normal Hold and Follow Hold functions CANNOT be used." I have both the WX5 and WX7. I also have both the VL70m and the WT11. The VL70m has a lot of better sounds, is editable and has better effects the WT11 allows you to use both follow modes. Any polyphonic midi keyboard with a midi in jack will allow you to use the follow modes. Read the directions on page 9 of your WX5 manual to hook your WX5 to the keyboard. Set your keyboard to receive all midi channels. I think it is Omni On, Poly. Hope this helps.

SOURCE: yamaha wx5 out of tune (1 tone to low) and pitch

As an electrical engineer, I suspect that one end of the resistance element or the voltage supplied to it is broken. This could be a broken circuit trace on a board or failure of the pitch wheel pot. This is iff the device has a center tapped pot. IF IT DOESN"T (schematics are hard to find on this) then the bias setting for the pitch wheel may be wrong. First thing would be to look if the the wheel has slipped on the control shaft.

SOURCE: My Yamaha PRS-293 will not play any of the E keys

The key switches are scanned as a matrix. One of the matrix wires has broken or connector/cable is not making it... It will be a connection in common with the non-working keys.

Here is schematic:

http://elektrotanya.com/yamaha_psr-293_sm.pdf/download.html

On page 40 on the board labelled 61H-MK and the connector DMLCD-CN401 the connections to pins 11 and 12 with signal names N14 and N24 have become broken or disconnected before they get to the processor board.

Since these lines are NEAR an edge, the cable could be not quite in the connector at one end or the other. These two wires are what triggers the E and the A# key signals. There are TWO contacts per key as one closes first then the other... this is how they measure key velocity.

Testimonial: "Thank you so much. You saved a good keyboard from going to a landfill! It was easy to fix with your information."