Chosen Solution
I have received an iPhone 7 that has been worked on before (badly). The faults were two fold, the first was no rear camera, this was the LDO near the Wifi IC which has been repaired by a previous tech. This tech also did an audio IC repair but has made a bit of a mash of it. ALL of the Pads along the top edge are missing. I have jumpered these are ALL of the diode readings are good without the IC on. I have replaced the Audio IC 3 times with new chips and still the problem exists. I have also replaced the speaker AMP next to tristar and the all diiode readings are good too. The problem is there is no audio, no mic input from the voice memo app and the volume buttons do nothing. Also there are no sw volume controls. I have also restored IOS twice. I am thinking that something is screwing with the I2S bus and before I start replacing the other amps and Maggie (which I have never had to do before) I was wondering if there are any other suggestions? All other features of the device seem to be working fine. (Oh and I have tried a different housing as well, so the fault is on the logic board
This is why I have stopped doing prior repair attempts. Assuming you know how to microsolder and the IC is going on correctly I would · Check R1103 and make sure it hasn’t been nudged off the back pad. The diode reading from C12 might seem okay even when R1103 has been nudged from the back pad but you will still have greyed out audio. This would be the most likely scenario. · Check the reset line at R3201 again check it hasn’t been nudged off the back pad. · Check the boost circuit. I usually give the IC a small nudge after it positions itself to make sure these pads are soldered correctly. I have also seen a faulty speaker amp to cause this but I would be looking at the prior repair attempt.
HI, did you get to the bottom of this as i have a similar problem, thank you.
