Motorola karma cell phone has water damage. the buttons work but screen display doesn't. when i turn on the phone, the screen flickers then goes black.

Hi, when ever a phone drops inside the water, first remove the battery cause the battery life might be damaged,and also in that process the phone is still working because the battery is still inside the phone.

You will need to service the phone for the phone to be free from water,cause if the water dries inside the phone it will damage an IC or a chip inside the phone and it might cause more damage to the phone.

After, disassembling the phone is the next step.
Get a phone screw and unscrew the phone from the back by removing the battery and you will see some screws, unscrew possible screws and open the phone.

Get a "methylated spirit"( check Google image) and a small brush, remove the board of the phone and deep the brush inside the methylated spirit,brush gently on the board of the phone. After brushing, get a dryer to dry up the board of the phone and live it for a while to dry.

After some minutes,assemble the phone back and fix in the battery. Make sure during the process you are charging the battery of the phone.

I guess that's all you need.

After doing these process, And still no luck, you will need to replace the flex of the phone.

Flex problem

The flex of the phone is located inside the phone, it controls the functions of the screen of the phone and it's controls the display of the phone.

The flex is a thread like object that is located inside the phone. To see the flex, you will need to disassemble the phone to get to the flex of the phone.

After replacing the phone flex, your done.

Also it might be the screen of the phone. But in other to know if it's the screen, you will need to test a new flex.

You can get a replacement flex from any of the phone repair stores around you.

Hope it helps.

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