Chosen Solution
Hi, I took out my iPad 4 after a year or so to find that the battery had swollen to an extent that it had separated the top right bit of screen off the body. I got a replacement battery and tried to replace it myself., followed the iFixit guide for it which was great. The device ran fine till the battery drained till 1% after which it turned off . While charging , the device does show the lightning symbol, but the charge percentage does not increase. The The Apple ipad charger/cable are known and working. I’ve tried the following so far: -Re-seated the logic board to make sure the pins were making good contact with the battery -Checked the voltage across the +/- of the replacement battery which showed 3.12V, does this mean that this battery is bad or is it just discharged? -Soft Reset(Home + Power) -Charging while powered off Is there anything else I can check to identify the root cause? I was considering the following: -Will putting the ipad into DFU help? -How can i identify a bad Tristar/U2 IC chip? -Is it possible that the swelling up off the old battery damaged something else in the circuit?
My guess is defective battery. At 1% it should at least be very close to 3.7V or higher. Starting voltage required to boot up system is around 3.7V. Lower than that the iPad should be on the low battery symbol instead.
