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So, i ordered an iphone 6 battery from amazon and replaced it properly without any damage. Everything went perfectly but after a few days the battery started draining VERY fast. It loses about 50% in an hour. I checked the battery capacity using different tools and they all say that battery is at 100% capacity. I even did the geekbench test to see the performance and the performance increased to the new iphone 6 level. I’m currently running ios 11.2.6. Tried everything from calibration to complete restore. Nothing works! What to do? PS: Also, I’m not able to see the battery usage statistics since replacement.
You either have a defective battery or there is something on the phone that drawing a lot of current. Does the phone get hot when it drains that quickly; if so, where? You could also try to disconnect some of the modular components, such as cameras, sensors etc to see if that stops the rapid drain. Sometimes, even though we think everything went smoothly, we can still do some damage to the flexes or connectors and that could cause battery drain issues. I would go back and double check your work and inspect the flexes and connectors under magnification.
