Question Should I attempt to repair my potentially failing Galaxy S7? (Intermittent black screen)

[ForsakenNGS]

Hi everyone,

some days ago the screen of my Galaxy S7 went black while using it. If I changed the angle I was holding the phone / tapped or shook it carefully the problem went away. For 1-2 days it was reproducable quite easily.
My guess what is causing this:

1. Loose flex cable
2. Corroded flex connector (the phone is IP68 "water resistant", but I assume over time repeated exposure to rain might reach the electronics after all)
3. Broken flex cable

After a few days, the issue has gone away completely now.

I looked up where the flex connector is and how I can reach it. It is on the back of the phone, which means I have to remove the back side, which is glass glued on. So I have to heat the back and pull the glass off the body which, according to ifixit, is hard and risky. I do have an ifixit-kit and am not hesitant to give repairing my suff a shot, but I do not have much experience with delicate electronics like phones yet.

My dilemma is, if the phone is corroding and I continue using it without dealing with that problem properly, as far as I know it might end up not being repairable anymore. If it is not, I might break a perfectly fine phone while trying to repair something that is not worth the risk. Coming to my concrete questions:

• Is there any way to judge which of the assumed issues is on hand? (Without opening it up)
• Does any of you have experience with this kind of issue?
• If I go ahead an open it up, what should I prepare? e.g. look for a replacement flex-cable if available, IPA for cleaning, glue for resealing (which one/type would you recommend?), etc.

Any feedback and suggestions are appreciated, thanks in advance.

Best regards
Jens

 

[helpstar]

Might be a software problem as well or a failing display

as long as it is working, don´t touch it

 

[ForsakenNGS]

Might be a software problem as well or a failing display

Based on the failure mode I am 99.9% certain it is a hardware issue and pretty sure it's a connection issue (loose flex cable, corroded contacts or broken conductor). Maybe the more unlikely option of a broken BGA joint of the graphics/display chip.