Yet another backlit Portable power problem---where to probe?

[stepleton]

Huh. Well, fair enough. Thanks for the quick reply.

The C116 issue gets deep into "ain't broke, don't fix" territory from the user's perspective, since contrast has always worked well enough for me. Considering that the negative terminal is tied to ground, maybe it's doing some kind of coupling or smoothing that we can get away without doing under most circumstances...

(NB: obviously I'm not an EE.)

(Also, just to check: does "contrast" mean the same thing as "backlight intensity" in this case?)

 

[stepleton]

Via rot around C11 brings the latest additions to the sad census: traces connecting U13C (buffer) pin 2 to U14J (VIA) pin 10, and U13C pin 12 to U14J pin 14 are also damaged. I'm curious what those buffers and that VIA do...

The positive leads of C10 and C11 both seem to be more or less on top of vias as well, and I'm not sure whether those are sound.