Chosen Solution
i have had this happen on a iPhone 5 and a iPhone 5s now, the phone is completely dead and wont turn on. tried every cable and power source possibly imagined. the phone will not charge. after replacing the battery the phone turns on and charges fine, but if the phone gets turned off or if the battery dies the iPhone stops charging??????? i monitor this by using a volt meter attached to the USB cable that tells me amps and volts of what the device is pulling for power and charge. so basically in short if the phone has enough power in the battery to turn on and start charging then it works great, but if you turn it off or the battery can not power the phone to the o.s. then it does nothing. has any one seen anything like this? i have stripped the phone from its shell and tested with new batteries and dock connectors, with no effect, the only thing running on the board a screen, battery, and charge port.
yes after doing some more search i found same thing a faulty u2 ic charging circuit. i did a hot air reflow to the chip and it seems to be working so far. i may have to re do the reflow with some flux but i think it may be ok. it has started to charge normally and is now recognizing dead batteries and charging them. at about 1 amp charge witch is pretty normal. also for any one looking at this post the u2 chips on a iphone 5 is located on the top side under the metal service panel near sim card tray, and the 5s it is on the back side under the metal service panel near top left side of the lower mount hole of motherboard close to the mobo antenna, i was working with a 5s this time so i just cut a medium size hole in panel and reflowed the chip with hot air. i would recommend using flux if you have it, and to let it cool down all the way atleast 30 mins, also if you do use flux then clean it up to best u can. thanks guys
Hi I have had this problem also but i found what i beleive is the issue it is the u2 ic. It controls the charging. If you google/youtube it you might find it answers your question. (i hope) Ps i am no expert
