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These problems HAve been related to a damaged flex cable.
This is the cable which in the U700 connect the lower part of the
phone to the lcd part (with the screen, speaker, camera and
touchscreen buttons). All
the data such as screen
images, camera pictures, speaker sounds pass through this cable from
the main board which is located in the lower part of the phone.
Unfortunately, each time
one opens the phone, the cable slides
between the two part of the phone. In the long term, as the cable is
thin and soft and this movement causes frictions between the cable and
the parts, the cable consumes itself. the damage of the cable could
results in weird effects on the phone.
In order to fix that you need to replace that part.its easy.
just take the phone apart and locate the flex cable and replace it.
believe me you can do it yourself.
- The Flex cable of your phone cost 3 $
- A phone repair shop will fix that for 25 $
see if you can find it on eBay.
remember its SCH-U700 Not SGH-U700 there is a big difference.Additional Help:Learn more about Flex Cables.Good Luck