c1200 is shorted and PMIC gets hot, needs PMIC replacement?
Hi,
Newbie here, just on my third iPhone repair (microsoldering) and wanted to get your feedback before I take off the PMIC and replace it.
I have a water damaged phone here, upon first inspection and after cleaning it didn't look so bad, but it was dead as a doornail. AMmeter does show 0.5a when I plug the logic board in (new battery, new dock connector, new screen). No sound/image though and the PMIC gets hot real fast.
Measuring caps along VCC main revealed a short to ground on C1200. I replaced that with a known good working one from a donor board, but the short is still there.
Seeing as PMIC gets hot as well, I think it's that that needs replacing or do you gurus have another thing I can try before I go that route ?
Thanks in advance for any tips !
Major update :
Turns out I was looking at the wrong spot the whole time. I thought the PMIC was getting hot, but in reality it was the CPU, a lot of caps near the CPU top row were also shorted out. Measured D1501 diode and only came out on 0.002, so the backlight diode was (one of the culprits), I suspect the backlight IC itself is also faulty. and maybe even the coil. I'll order a set of those and give it one last try.
I didn't think it would be 'just' a backlight issue, since I tried shining with a heavy duty flashlight through the back of the lcd and nothing appeared, but I guess a faulty backlight coil/ic/diode could cause these symptoms ?
This is really a rabbit hole, I don't think I'm a big fan of waterdamage repairs :)
Is this a good question?
2 Comments
How long was it in the water and where did the water get most?
by Gigabit87898
Just dropped in the toilet and the owner grabbed it out rightaway. Fully submerged. Most water was in the top, near the camera connector. Upon doing a second sweep I found a couple of caps that are shorted near the PM8019 IC. And.. I also found a solderball... argh..
by Dennis Meerveld