MARIKO board has less than 20 ohm on that 0.8v line, how much resistance there you call it short?
i get about 15 ohm on that side, board is a HAD-CPU-10 and my max chip has a H at the end.
exactly, v2 board I got mine at 16.8 ohm on that line. So thats not a short.
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Oh snap!!! Thank you, love you jkyoho, im am now going to try to boot into os.
I think i have bad news, i injected voltage using 1 wire on the usb-c port and 1 wire on the coil next to the BQ chip and it reads 0.7xx amps at 4 volts, Max gets hot as helllllll also the cpu gets warmer than the areas around it? Need some advice should make it a parts board or go for the cpu re-ball?
what where why
how much current draw from charge port without battery plugin
I got this board in pretty bad shape, the shield over the CPU looks a lil brown so I’m suspecting someone tried to maybe reflow or reballed the ram, right now there is no usb-c port so I can’t check what the amperage would be, I can throw one on in the morning and check
I took off I took off the shield and this is what I found 
it looks hella crispy
definitely been BBQ both APU and RAM. Donor Board pile confirmed
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i ordered a cpu stencil, i am going to try to reball it and see i can get any improvement. for fun lol
SoC looks fine and doesn’t seem as though it’s been reworked, the flux around is is likely just because it’s wicked up the shield by the person who did the Ram reflow.
If your going to proceed I’d first determine if you have a short on your SYS rail and if yes identify that first (you should also check all your other primary rails too ie: check the resistance to ground) by the sounds of it it’s the Max IC which is responsible (though it’s not clear which one your referring to?) , if/when you resolve that issue then proceed by reballing the Ram. Given the SoC is getting hot it’s entirely possible it’s dead already 
For future reference you shouldn’t be applying voltage willy nilly to seemingly shorted rails (at least not at this stage at these voltages) rail could potentially not be enabled ordinarily as a result of OCP/short circuit protection which might prevent damage downstream (for example a short from your SYS rail to a CPU line for example) which could possibly save it (this is just an example mind you) in which case you’ve just bypassed this and killed it yourself (again, just an example, you might not have)
You might want to take photos of the board front and back for your reference later (incase liquid damae, clues etc) .then Ultrasonic the board as it’s in desperate need of a bath
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with no emmc its pulling a little above 1 amp.
I checked everything and everything looked good the only thing i found shorted was that cpu cap below the m92 and that one cap above MAX77620H, after reballing the MAX77620H the shorts were gone.
it shouldn’t be, it’s implying you have something else shorted which shouldn’t be. check your other rails. I presume this is via USB? (you should probably avoid plugging this board in/connecting battery in it’s current state anyway)
It’s not a CPU cap, it’s 1V8PDR/ pretty well everything is connected to this rail.
Was this PMIC poorly reworked prior like the Ram?
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MY BAD! its pulling 0.1 amps
Sorry about that new to fixing electronics so i can only reference it as what I’ve seen the most referred to (cpu cap LOL).
Yea it looks like the previous owner Re-balling the PMIC or maybe they just reflowed it? was poorly done due to after my attempt reball the short 1v8 short was gone on those caps and everything checks out now, worried that this short might have killed the soc or ram especially after injecting that voltage.
So far my next steps is to reball the ram, and if that doesnt work make it parts board 
. Really demotivating i thought i could save this one.
Seems normal without emmc but CPU should not go hot in that case. Warm but def not hot
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No worries, that seems more like normal
It’s not your fault. I’ve seen quite a few people refering to this rail as the “CPU rail” and in turn that cap below M92 which resides on said rail as the “CPU cap” … not really sure where that all started but what you’ll find as you become more experienced is the repair community (particularly the youtube repair crowd) is it’s a vaccum and it only takes one person to get something wrong or to do something stupid and others who don’t know any better will copy and the cycle repeats… for example, one idiot starts using a rotary tool with a diamond bur to remove solder mask <0.1mm thick (the same bur I’d use to drill holes in masonary, tiles or glass) and then every man and his dog starts doing the same thing 
That all being said, the SoC is also connected to this rail but so is pretty much everything else - it’s produced by the PMIC which is why after you reballed it seemingly cleared the short here.
Yeah could be. It’s entirely possible now though, given that this IC produces some all important rails for the SoC and if things were touching which ought not to have that the SoC may have died, or the PMIC might be bad in and of itself.
Don’t be, this board looks like it’s been through the wars anyway… plus it’s alway nice to have a parts board 
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These are my next actions.
imma re-ball the ram first and then the soc for fun and see what happens, also i already made the purchase for the SOC stencil so its to late now LOL, its good practice either way.
As for parts, Do you think the PMIC chips are still good in this case? I’ve read they don’t really go bad in other posts here.
im thinking when i reball i should inject voltage again at the coil and see if it still shorts as i take the ram and soc off
Just a word of warning if you don’t know already, you want to get the 80x80 or 90x90 stencil in combination with the jig and preformed balls for the SoC. A direct heat stencil and solder paste won’t work (or rather your setting yourself up for failure with this type) I’d start with Ram first and go from there.
Details regarding the jig here
don’t know if I covered the stencil to use along with it for the SoC in that topic but it will be there or somewhere else on the forum somewhere 
Under normal circumstances the PMIC is quite resiliant but in cases like this where somebody prior has purposely messed with it it’s hard to say, all depends on what was going on below it after he/she messed with it…
No, search the forum regarding checking your primary rails (resistance relative to ground) which I’ve covered a bunch here to get an idea of if anything is still shorted out and to get a map of the current state of things - if everything checks out then you atleast know what is good if/when you start reballing Ram, PMIC and later SoC (in the event your install goes bad or you damage the chip/s during reflow) all of which you’ll be able to test prior to ever connecteing power (far safer) and/or you find the short and in doing so you’ll be able to determine if pulling the IC’s we’ve discussed resolves the issue (whihc we can narrow down if you do find something) - what you were doing earlier was connecting power up to your SYS rail (which is basically the source voltage for most things and pretty well every other rail derives from it in some way shape or form), subsequent short on 1V8PDR (possibly dragging SYS down as a result) trouble is/was your putting other things in the line of fire doing this.
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