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Yeah, I do have a few scrap boards, but that mosfet is a raw die BGA. I haven't had much success trying to reball those in the past, unlike regular BGA packages. Not quite sure why.

Yeah sorry about the quote, I don't usually do that. Not sure why I did it here, my mistake. So, I have removed the mosfet, and I now see about 1kohm to ground on PP3V3_S0, which looks much better. I don't have a replacement mosfet at hand, so I'll have to get some from aliexpress and it will...

I don't really know the history. I got this board from a joblot off ebay. At first it was totally missing PP3V3_S0, with a dead short to ground. There was clear signs of liquid spill in the corner near the headphones jack, and especially, the microphone ribbon cable connector looked really...

Hi, I've got this board and it's giving me trouble. It will not start because PP3V3_S0 only has 1.8V When I measure resistance to ground, I get about 130 Ohms, while a good board has approx 1KOhm Thing is 130 Ohms is too much to be able to get the bad guy to get hot enough to find it. I've...

I think I found the post you were referring to: https://boards.rossmanngroup.com/threads/820-01700-05-a2141-lcd-issues.58546/post-58568 It's not about the same model, in that case it's a A2141. But basically duke was saying that the display from a non-true tone machine would work in a machine...

Ah ok. I did try to search for this in the forum before posting but didn't manage to find anything useful. I'll try again, targeting specifically duke's posts. And if nothing, I'll cross check one more time the connector pinout to check that signals are indeed compatible, and if so, I'll just...

There's no client. It's just me collecting dead macbooks from here and there and messing arround with them on my spare time. So nobody will "not accept it" in this case (besides myself) ;) Yeah, I was also thinking about that True tone thing, which is why I asked the question both ways. I think...

Hi, I've got a display that comes from a dead A2159 and I don't have another machine of that kind to test it. Physically it looks similar to the display of an A1708. Are they compatible parts ? Can I put it in an A1708 in order to test it ? And then, for the sake of completeness, same question...

Hi, I got a liquid damaged board that doesn't manage to get 20V from the charger. From the corroded areas, it is pretty clear to me that the top left CD3215 (UB400) is, among all 4, the one that's causing trouble. Another hint is that I get power loop on 3 of the ports, and on the last one, I...

Didn't manage to find a clean ME BIOS. I took a dump from a dead CPU donor board and flashed it on this board. Same problem. No PPVCCCPU_S0G and no PPVCCGT_S0G. When plugging in the charger, PM_EN_CPUVCC goes high, then low, then high and remains high.

Yeah, PM_EN_CPUVCC is high, I forgot to mention that. OK, so I will try to play with the BIOS. I'll start dumping the existing one, just to be safe. But then, what should I be doing ? Can I just pick a dump from another board just as is ? I guess this will have ME issues, but maybe it's still...

Allright, the caps were not causing that issue. It took me a while to get a new PMIC in order to replace U7800, but I finally got it yesterday and replaced the chip. The board still doesn't boot, however I am now getting a lot more power rails. In fact, all rails are present, except for...

I already had the coil resoldered from before. Pin 23 has 13 volts Pin 12 has 0 volts Pin 13 has 0 volts Pin 22 has 3.3 volts Pin 29 has 0 volts Pin 21 has 0 volts Looks like I'm missing the enable signals for the rails. I went on and checked the U7890 gate that controls PM_EN_PVXS5, it has...

Hi, So, with the coil lifted, the short was remaining on the filter cap side. So I tried to inject voltage. At first I sent 1V, but not much happenned. Then I went for 3.3V. I could see it was drawing between 200mA and 300mA for some time, but while I was trying to feel heat on the board, I saw...

Hi, I am practising with another 820-00840-A board that does not turn on. There is no sign of liquid damage. My charger gives 20V so I have PPBUS_G3H. PP3V3_G3H gives me 3.41V Then my S5 rails are all missing. I figured that PP3V3_S5 reads 7 Ohms to ground. I suppose this means a short to...

OK, I have lifted all three coils. They all have a high resistance to ground on their regulator side, but still about 3 Ohms to ground on their CPU side. PPBUS_G3H is no longer shorted to ground. I haven't tried to power the board without the coils in order to see if I get proper voltage there...

Yeah well, then this is not one mosfet to remove. CPU VCCGT has 3 phases and there is no external mosfet, they must be directly in the regulator chips (U7410 U7420 and U7430). I guess I don't really have a way to know which one has the short, so I have to remove them one by one until the short...

So, if I understand well, I should compare my ohms to ground for PPBUS_G3H and my power rails coils. The idea is to check if I'm getting similar readings, which would indicate that this rail would be shorted to PPBUS_G3H right ? In fact, I'm seeing 3.97 Ohms between PPBUS_G3H and ground, and...

Hi, I have acquired a liquid damaged A1708, for practicing purpose. I am certain this laptop has never been touched, there has been no prior attempt to repair it as I know the previous owner who is responsible for the spill. The CD3215s look fine as my charger goes to 20V, however the board only...

Yep, that worked. Thanks! Out of curiosity, did you start from my dump file at all ? Or did you use another, not corrupted, dump and replaced S/N in there (and fix checksum and ME stuff) ? One day I'd like to learn how to do this by myself, but so far I haven't been able to find good documentation.