Burnt out neck LEDs :-(

[BeenDown139]

so i went to work the ebony amazon out this afternoon, happen to look down at the neck and i noticed that i now have 2 dark LEDs. the one at the 19th fret must've died between last night and today.  the one at the 21st was out when i bought it.  has anyone else had this happen?  this bass gets played alot.  but it's always (AFAIK) handled with care, never dropped or jarred.  the upper register LED string on my 4-string fretless only lights up in the summer after it gets hot and dry here in the mile high city, so i suspect its issue is a wire getting pinched when the neck wood adsorbs humidity.  i'm gonna guess this can only be remediated by peeling the fingerboard in either case.  is that correct?  any advice/sympathy appreciated.

[mica]

It's very unusual to have a dark LED, but first,  are these turned down to a very low brightness? Often the components turn on with slightly different voltages, so very dim settings can produce this result. Otherwise you are correct that repair means removing the fingerboard. Let me know what happens when you turn up the brightness trimmer inside the bass.

[rv_bass]

There is a small circuit board inside the control cavity that is associated with the dimmer control knob. You might want to start with checking to see if all of the connections on that board are still working.

[BeenDown139]

thanks for your replies mica and robert.  i tried the LED intensity control with no improvement. i do run these at a low intensity.  the engineering dude that lives in my head suspects that the LEDs are connected in series.  the red ones have a different forward voltage than the blue ones so they have seperate circuits.  poking around in the control cavity seems to confirm this.   i'm probably fortunate that the LED failed shorted so the rest of the string still functions, sorta like old-school xmas light strings.  these LEDS are run at very low current (~6 mA) so having them fail in normal use like this is concerning.  they're not subjected to heat or environmental abuse.  they're fed by a line isolated DC source so they're not subject to reverse voltage or spikes.  an LED in this kind of application should last practically forever.
in the case of the A-Bass the whole upper register LED string has failed.  i've traced the faliure to an electrical issue under the fingerboard.  i would suspect for the SII, it's a component failure.  in either case they're unfixable except by perfoming a very invasive and expensive repair to the bass(es), so i guess it'll be my kid's problem when they try to sell them after i kick hte bucket. 
i lit the A-bass up to take a picture for this post.  it's been an exceptionally dry winter here in the mile high city, so the fingerboard has been drying out (and shrinking i suspect.  i'll find out when i tune it up later today)  you can see the upper register string just starting to come back on.  if the neck fully dries out, i'll get full intensity out of it.  normally this doesn't happen till around june.