1V8PDR resistance to ground (more or less identical both ways):
- BSOD board → 500 Ohms
- Donor boards → 1.8 kOhms
Something’s going on here. If I follow your logic, since the SD connector was crushed, maybe the SoC took a hit?
Yeah primarily because of this the SoC is likely toast I’m afraid (which is why I say check your primary rails first, and consistently 
) but it’s together with the other info too such as the issues at the PI3 and back at the alert line etc. I’d imagine if you pulled the SoC the 500ohm high “short” would clear.(assuming nothing else was taken out in the process)
btw your meter seems a bit rubbish, I’d reccomend UT61E meter for more reliable and accurate in circuit readings 
fine in this case as it’s relative to other board measurments but might save you some headaches in the future.
Yeah absolutely, 1V8PDR is present at the SD connector, so this could also be a factor, SD lines go off to the SoC directly 
You mean, like, in almost every post whereas I kept saying it’s fine because the diode readings were right, but didn’t bother to check the resistance to ground? I don’t know what you’re talking about 
As my parents used to say (they were teachers): repetition is the mother of all learning.
Anyhow, I removed the fuel gauge just in case. It changed nothing (neither the readings, or the RCM mode), so it wasn’t at fault.
I guess it’s time to remove that SoC, see if that relieves the “short” on 1V8, and slap another SoC back on!
Haha yeah. Think of diode mode as the low res CRT, gives incredile contrast but the resolution and picture quality is poor (diode mode is great for pass or fails but terrible anywhere in between) then think of resistance mode as a high resolution LCD 4K TV with fantastic picture quality but compatively poor contrast / black levels. Contrary to most of the [idiots/misinformed] youtubers, you wanna be in resistance mode 9/10 outside of the quick and dirty pass/fail mentioned, that is unless you wanna chase your tail and waste time that all being said your particular meter isn’t going to be the best showcase of this but hopefully you see my point
wise words.
might also wanna pull the P13 IC too and check those lines, pads and the filter, and make doubly sure there is no junk in the USB port or bent pins etc, infact, I’d probably pull (and replcace later) both the P13 IIC and the M92 IC , last thing you wanna do is replace the SoC and then instantly fry it when pluggin it in, better safe than sorry.
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So I finally removed the SoC, to see whether that relieved the short or not. And it did, 1V8 got back to 2kOhms (no longer 500 Ohms) so the only logical conclusion is that the SoC was bad.
As usual, thanks for helping, @Severence .
Glad you got that confirmed.
Might wanna check the corresponding cap which is on 1V8PDR on the SoC wafer (should be able to buzz this out on another board to find the cap in question) and check resistance again just to rule out the SoC issues being as a result of a bad reflow… I don’t think it will be tbh given the issues you saw at the P13 IC which is pretty synonyms with SoC death.
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