"Jerry" wrote in
:

Thanks Larry for the very informative feedback but the problem goes
further than that and maybe I didn't explain myself clearly enough.
If I'm watching the screen scrolling by with fish or not, all of a
sudden the display ends with a dark vertical black line and just a
clear empty screen following it. I can stay clear for a 1/4" width or
a 1" width up to a full screen width before I see another dark
vertical line followed by the normal display of the bottom and fish if
there are any. It has gotten so bad that I'm now getting a 1/2" of
display, a vertical line followed by a 1/2" of blank screen, a
vertical line, then another 1/2" of display, then a vertical line
followed by a 1/2" of blank screen, a vertical line, and this may go
on repeatedly forever. Sometimes if I shut it off and wait awhile it
may work okay for a minute or so and then it starts to act up again.


Now that sounds like the heat from the sun is expanding the LCD screen
enough so that the rubber conductors along the edges isn't making proper
contact. The service center probably wouldn't find it because where they
tested it it was air conditioned and cool, not nearly too hot to touch.

Is the display unit sitting out where the sun shines on it, like in an
open boat? LCD means Liquid Crystal Display. The crystal part is very
tiny particles suspended in a gel-like material like one of those squishy
insoles from Dr Scholl's. The problem with LCD is it MELTS! If you get
the display too hot, it will just turn BLACK because the reflective
crystals have melted and can't reflect light. As soon as you cool it
down, they'll start working again, unless it has really gone way too far
hot, which destroys them. The no-current, very high voltage the LCD
display works from is conducted to the glass carrier you're looking
through to extremely fine, nearly transparent conductors painted onto the
display surface in a very fine grid pattern. Where two of these
conductors cross, if we put high voltage between the conductors, the
crystals in the display are lined up so light passes through. Color
displays just have more layers. It's very complex. To connect the glass
to the box, a rubber tube holds the display glass in a holder. Buried in
the rubber tube from side to side across the round part, are thousands of
tiny conductive particles insulated from each other along the length of
the tube. The contacts in the frame touch one side of the tube, the
contacts in the glass touch the other. Obviously, if any water gets into
there, that isn't going to happen. Alignment is also a problem the tight
carrier is supposed to solve. Perhaps yours has come loose so it can
misalign in the heat when the glass expands at a different rate than the
frame. You probably can't see it from the outside.

Call the service center and exactly describe what is happening to the LCD
display and at what temperature/humidity conditions. I think you have a
defective or misaligned display. The sonar part is probably fine.....you
just can't see it.



--
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.