Registration Lights do not all work

[Kurzweil]

I just bought a used PX-5s, probably from 2016.  BANK, 0, 2, 3, 5, 7, & 8 LEDs all work.  I have yet to see 1, 4, 6, and 9 indicators come on.  It already seemed strange that the top row has independent lights (bank and 1 thru 4) while the second row integrates the lights with the buttons (5 thru 9).   This model is quite different from my past Privias (100, 310, and 330) but I suspect that I have four dead LEDs.  Fortunately, the display duplicates the information but it's a mite disappointing.  Note that the buttons themselves work fine.

 

Giving it some thought and the regular pattern of the missing lights (1 is above 6 and 4 is above 9) leads me to believe that there is a fault and it is in the wiring to the display/button assembly.  It looks like a matrix issue.  I had an issue with a Kurzweil PC3x that turned out to be a connector that had not been pushed all of the way in, presumably during assembly.  It caused the unit to occasionally fail to boot and could be temporarily bypassed by a sharp rap upon the case with the hand palm.  The likelihood of four failed LEDs is near zero.

I love that I play a black keyboard if in right profile and a white one in left profile.