Chosen Solution
Hello, I replaced my iPhone 4 screen and digitizer as the previous one I had attached was cracked. After putting all the screws back in there original places I fitted in the battery and screwed it down where it connects to the motherboard. I placed the back cover on and screwed it in. Over the next few hours the iPhone would randomly just shut off, and in order for me to restart it i had to take the back cover off, take out the battery and then put the battery back in again. I am stuck as the exact same thing has happened again, but this time when i go to turn on the iPhone it will not load past the apple screen and after a few seconds it shuts off I would really appreciate it if i could have some help on what to do to fix it. Ben
It does sound like you have damaged the battery replace it and you will know
Check to see if you have accidentally torn the battery connector socket from its solder pads on the logic board–sounds like this is the problem. Jessa