Chosen Solution
I dropped a jug-full on my iPhone 7 overnight. It wouldn’t have been so much of a problem if there wasn’t a giant hole in the bottom-right of my screen, but it happened. Opening my phone, there were water droplets in the center, and the lightning connector mechanism and the home button were completely rusted. I cleaned up some parts of the phone that seemed to have damage on it with WD-40, but the thing that fixed some of the phone was the underside of the bottom-right of the logic board. When I turned on my phone, (after charging the battery with my iPhone 6), nothing happened aside from the Taptic Engine responding whenever I clicked the home button. Right now what I’m planning to do is opening up the protective covering on the underside of the phone near the bottom to see if I can find any damage and use some 91% Isopropyl Alcohol and a toothbrush to try and fix it, but I don’t know how to put the covering back on after I take it off. Also, I purchased a new screen because I thought the old LCD might’ve been defective, but I got the same results as the last one. The lightning connector is picking up 5-Volts with a multimeter, but when I plug it back in to the logic board, I don’t think it’s charging at all. Also, some more components might be defective because when I tried to use the ringer switch to see if it would buzz, nothing happened. But this might be because it wasn’t working properly from before I fixed it. So basically, should I go ahead and take out the protective casing covering the pins on the logic board, and how would I put the casing back on? Any Ideas? Thanks.
On the iPhone 7, the backside of the logic board is covered with a paper-like cover. You can just peel them off. If your careful, you’ll be able to put them back on and they will adhere enough. Worse case, you can always put some Kapton tape. The other area where you can get corrosion is underneath the CPU shield. That one must be unsoldered, preferably with a hot air station because you have to get just enough heat to get the low-melt solder to flow, not too much to damage the solder balls under the CPU. Based on your description, it sounds as if the phone is booting. Have you tried connecting it to iTunes to confirm? If it is, then your problem may be with the Backlight/LCD driver circuit.
