Chosen Solution
Hello, After I replaced battery on my IPAD 3 (4G), currently I experience issue with it since it restarts itself every 2-3min. I read the other forum topics and understood that the problem might be due to a fake battery but I bought another battery and tried with it. Unfortunately the results was the same - IPAD restarts in every 2-3min. In general, when the IPAD is switched on, it searches for mobile network, while it is connected to WI-FI and after it can not find any network, it restarts. This trend is based on my observation and it does not matter if there is SIM card inserted or not. My concern is related that the IPAD can not detect the 4G module correctly, it is connected to the mother board but still it is strange. Would you please be able to suggest any solutions for this issue? It will be very helpful because at the moment, it is useless like that. Thank you. Update (02/05/2018)
A bad battery is the typical issue for these kinds of symptoms. However, after trying two different batteries, it may not be the case here. To know for certain, measure the voltage of the battery directly (while removed from the iPad) with a multimeter. If you are measuring more than 3.5V, the the device should boot fine. If the voltage looks good, then you may have damaged something when you disassembled the iPad. Check the logic board in the connector area and inspect the flex cables for tears, even tiny ones.
battrey is bad change new one
if possible do a factory reset via itunes on your computer. while typically this would be caused by a bad battery or such, I have seen software issues do weird things before, especially on iOS devices
