I just got a 102 off eBay today. It was sold as working, but
arrived
with four dead lines in the LCD. They’re horizontal, from the 2nd
row, and repeat every 16 pixels.
I opened it up and it worked fine. I figured it was the cable, so
I
sprayed some DeOxIt in there and put it back together, only to
find
the problem was back again. Taking a closer look, there’s
something
making marginal contact on the LCD board. When it’s flexed
slightly,
the lines vanish, and the case presses on it just enough to make
the
problem crop up.
It felt like a bad solder joint to me, but after inspecting every
connection with a 20x loupe, I didn’t see anything obviously
wrong. I
suppose that still might be the case, since it’s awful hard to see
the
tiny SMD joints, even at 20x.
Is there a common failure mode for these panels or something else
I
should be looking at?
Based on my reading of the schematic and tapping around, I
suspected
M11 might have a marginal connection, so I resoldered all its legs
--
still nothing.
I don’t see how the panel itself is connected to the PCB. Perhaps
there are pads on the top side and it’s simply the friction of the
panel sitting on the board that does it? The more I poke around,
the
more I think it might be the PCB to panel connection.
Any suggestions on what to look at to get this machine 100%?
-- Ian
