Chosen Solution
My Iphone 6 was functioning properly battery wise on my first year of usage, after i updated to IOS 9.2 the problem started showing, where i left it on 100% off charge one night and woke up the next day 8 hours later with 20% . Methods tried I followed and contacted apple in which they tell you what to switch and what not to switch in order to maximise your batter life (It only wasted my time and DID NOT WORK). Disabling settings (DID NOT WORK) Deleting certain apps (DID NOT WORK) Setting up the phone as new (DID NOT WORK) They advised me to replace my battery and i did (Again it DID NOT WORK). My battery during usage only lasts to 3 - 4 hours max And dies when it is on standby mode in approximately 7-8 hours without using the phone. Kindly if your phone has started battery draining after updating into a certain IOS HELP A BROTHER UP ! :(
I’ve ran into this issue many times, and the problem lies within the board. The U2 IC chip causes quick battery drain, as well as charging issues. It is a board level repair, and Jessa over at iPad rehab has repaired a lot of these. Typically, the U2 IC chip gets fried from third party/aftermarket chargers and blocks.
