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Fixing cracked solder balls under a BGA package

I got another pack of failed Xbox One controllers. Most of them had classic problems like broken LT frames,(which by the way I could not find anywhere) broken analog sticks and broken internal board-to-board connectors.
I noticed that one of these controllers was the strangest of all. Everything working fine with this controller except the LT and the Y axis of the left analog stick. I walked through my regular troubleshooting process and I didn't find anything unusual wrong. It discovered later that was a cracked solder ball under the main controller chip. The crack was probably caused by a strong external force like a drop or a bend.
As I continued repairing this poor gizmo, I realized if I pushed the IC to the board with my finger I get the right values on my tester and everything seems to work as it should. This ment that the cracked balls maybe fixable by a reflow so I reflowed the chip but it did not worked. I wanted to try to fix it by doing a reball, but I don't have proper equipments for that kind of process.
I saw a video made by a professional controller repair company that discussed these types of controller failures so I decided to try to implement the tips I saw in the video. I did not want to desolder the chip because I could not put it back. I needed to figure out how can I get as close as possible to the cracked balls so I carefully started to remove the epoxy body of the chip until I reached the cracked balls. Luckily the IC did not brake under the process.
I fixed the cracked balls, by using really fine wire. The balls were not reachable by the soldering iron tip itself, so with the wire, I could transfer the heat right to melt the cracked balls. 
I think I fixed this issue as cheaply and professionaly as I could and I took my soldering skill to the next level.
Here is some pictures of repair:
Cracked solder balls marked on another motherboard 
LT ball is exposed

Almost done 



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