Iphone 5S battery issue
 

Hello, i have 5S hot, and drain battery. when connect to cable, he charging good.
How can i test if it's U2 ic before replace.
Thanks

History of phone if batt has been replaced or not then if batt drain very quick like 2-3 from 100 means charging ic and once compeletly drain then dont charge

customers say me little water damage, the board are clean..
When i charging, the phone are hot, but he charge good. he lose 1% per seconde.
i would like to test tristar ic before replace, but i can't how test it (caps near for volt?)

Up; phone charging ok, he are hot, but drain 1% /min.
U2 ic can be create hot phone ?
CPu are hot, and Amp are instable.
(i remove camera, sensor facetime, new batterie, disconnect home button)