Worn out bsttery
This was my first time replacing batteries in iPhones. The repair went well. I actually replaced batteries in 2 phones and, after finishing the first one, the second one was much easier.
Two things. (1) I found the quality of manufacture of the philips screws to be lacking. One pair worked as advertised but the other pair would not go in all the way. I also found the pentalobe screws held onto the driver way better than the philips did onto their driver which made it easier to screw them in. I resolved since I now own a pentalobe screw driver I would use those screws. (2) I found the bend on the flex cable coming off the battery needed to be shaped properly. I figured out how to do this by trial and error and observing the old battery. This is delicate operation which requires patients a light touch and the proper tools. This was not mentioned in the instructions or any video on utube.