820-00875 Dead

- No liquid damage
- Fixed short on PP3V3S5 FET.
- PPVIN = 20v
- Several short (?0.1 ohm) on U7800 (PMIC) rails
** PP1V8_S5G

Lifted coils for the last 2 and both have the short on the load side a.k.a. CPU/PCH. Of course, the CPU could be shorted. Would it also be possible there's one common short somewhere, causing these rails to short through the CPU? Any suggestions on how to proceed?


Staff member
I have NEVER saw multiple short on CPU (or other common component), caused by other different things!

Very easy to discard.
Choose the higher voltage and lower short value from al these power rails.
Inject volyage there and check if CPU heats...
Just tested and both PP1V8_S5G and PPVCCPCH_S5G cause the CPU to heat when voltage is injected. I also noticed U7800 (PMIC) getting warm. Would it be wise to try change this, or should I assume it's the CPU at this point. This would be 3 in a row for me (2 A1534's though, these don't count :))


Super Moderator
Staff member
I wouldn't waste time with this. These boards (00875 and 00840) are awful. Almost every one I see in my shop has a shorted CPU or does not post from a dead CPU.
Ok, good to know. Not really up to speed on repairability of these "new" types. Thanks for your help guys, this is a no-fix.