Chosen Solution
So i recieved an iphone 7 that had the audio ic replaced. The customer said that it doesnt vibrate and people can not hear them as well as putting it on speaker changes nothing and sound still comes through the top speaker. I tested everything and they are correct about all of the issues. Also they stated that it will restart randomly for no reason. If any one could help me narrow down what’s wrong with this board I would greatly appreciate it. Thank you all in advance!
The first thing to suspect is that the Audio IC repair didn’t go smoothly. If the “new” symptoms roughly correspond to the Audio IC repair, then I would inspect the workmanship and use that as a clue. Assuming the Audio IC was properly replaced (with jumper on C12 at least) and there no obvious signs of missing, dislodged or bridged components, then I would start probing the the ARC circuit (taptic engine) and work my way from there.
