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I replaced the battery in my iphone 5 with the replacement kit from ifixit today. Before the replacement, my phone’s battery slowly died even while it was plugged in. I assumed the battery went bad and replaced it once it died fully and wouldn’t charge or turn on. I watched the youtube video and followed the steps for battery replacement but something must have gone wrong. Now my phone will not turn on. When I plug it into my computer, my itunes recognizes it right away with a 38% battery life. It seems to not be the battery. I double checked all connections I touched to make sure they were securely reattached, and they were. What else should I be looking at? Most answers I’ve found to similar questions first mention the ribbon cables. I know ribbon cables are very delicate(I’ve worked in electro-mechanical assembly) because I’ve dealt with them before and I was very careful with them. What should I be looking at now? Thank you in advance for any help I get with this.
You may have blown the backlight circuit on the logic board. To test this, plug your phone into an iTunes enabled computer and then shine a bright light on the screen. If you can see a dim image, then your backlight is defective. It could either be the screen itself or the backlight circuit. Did you disconnect the battery before disconnecting the screen? If not, then your problem would be with the backlight circuit. This will require a micro-soldering repair and may not be economically viable depending on the value of the phone in your area.