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820-00875-a - a1708 - frying SSD'S

2informaticos

2informaticos

Administrator
Staff member
First of all, welcome to the forum!

I hope nobody insert/remove SSD without disconnecting first the battery.
PPBUS_G3H is present on J8600.

Check voltage at pins 1 & 56 of J8600; without battery connected, only charger.
 
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Anterweb

Anterweb

Member
2informaticos said:
First of all, welcome to the forum!

I hope nobody insert/remove SSD without disconnecting first the battery.
PPBUS_G3H is present on J8600.

Check voltage at pins 1 &56 of J8600; without battery connected, only charger.
Click to expand...

Thanks for the quick response!

I have no clue what anyone may have done before I got my hands on this but no removing of SSD with any power attached on my watch!

J8600 voltages
Pin 1 = 13.02V
Pin 56 = 3.31V

Thanks in advance

Ant
 
2informaticos

2informaticos

Administrator
Staff member
I specified that because I saw damaged SSD caused by this.
Is sufficient to disconnect battery data flex; no need to remove battery screw.

However your power rails look good; no reason for overvoltage damage.
NVME adapter should not even use PPBUS_G3H.

BTW, write directly into reply box, instead of clicking Reply button.
I don't see any reason to quote an entire post, visible few centimeters above.
Please, maintain forum aesthetic...
 
Anterweb

Anterweb

Member
Gotcha with the reply's (y)

So where can I go from here, am I to presume the logic board is good and not causing this issue? Is there anything else I can check that may be causing it? or do I just take it as bad luck that 2 SSD drives died and try my luck buying another one?

I'm reluctant to try this considering how hot my Samsung Nvme windows drive got and the fact I get no fan spin at all but I'm still unsure if this is normal or not in this model and these SSD drives are damn expensive!

(Are either of these non-responsive apple SSD's repairable or are they both now trash?)
 
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2informaticos

2informaticos

Administrator
Staff member
You've said your Windows NVME SSD got hot, but survived?

Did you test without fixing the bottom cover?
The fan should spin when CPU gets hot.
Check CPU temp with some specific software; HWSensors recommended by macOS.
 
Anterweb

Anterweb

Member
Yes the NVME got super burn ur balls off hot, it happened really quick and yes I had the rear case off and could feel the heat through my trousers burning my leg so shut it down stat!, I think this is what saved this drive as if it was on the workbench I would have not noticed the heat and my drive would have been toast!

I installed HWSenors ( great app!, thanks ) and with some HD video playing for a while these are my temps, It took a while but once warmed up the Exhaust digit went up from 0 and I peeled back the back cover to confirm that yes the fan was spinning,
hwmonitor.jpg
I tried both original SSD drives again, still no dice
Im at a loss as to what to try next. The Mac has been running for over an hour again tonight from the external HDD without any issues , It just won't see or function from an internal one.
 
Anterweb

Anterweb

Member
Removed L8600 and now it dosent see the nvme at all, tried both the new one I have and the Samsung evo with Windows on and I just get the flashing folder icon and can't see either drive in disk utility.
Still boots fine from external drive.
 
Anterweb

Anterweb

Member
So seen your message this morning and stuck the logic board under the scope to do as sujested and removed L8600 and replaced with a tiny jumper wire, but in the process I blew the C8601 cap right next to it clean across my desk never to be seen again! (noob move I should of had a coffee before starting this!)
I don't have any spares so have ordered some but will take a couple of days to arrive. I checked board view and checked voltages and still have 3.3v going to all the places it should with the wire in place of L8600, but on putting the board back on the machine turns on but I have no display. No sign of life from the screen, but I do get touch pad click, USB lights and can feel the cpu getting warm.
Should I reinstall L8600 or wait for these caps to turn up? (looking at the BV it dosent seem like that missing cap should stop the screen from working?)
 
Anterweb

Anterweb

Member
I have 3v3 at all relevant spots on J8600 but still no life on the screen, seems to power on have touch pad clicks that stay present for a bit then stop then start again like it's power cycling, but dosent turn on to the point I get anything on the display
 
Anterweb

Anterweb

Member
Same result, Nothing, I notice while doing this I get touch pad click for 10 seconds then it stops for 5 seconds then back for 10 seconds and so on....

I also noticed I cant power this on with the battery disconnected is that normal for this model?
 
Anterweb

Anterweb

Member
So I pull out the logic board to test as something just didn't feel right after adding the jumper wire then getting no display. after testing I find that R5515 (current sense ) is shorting and sending continuity all over the place, It must have taken a hit yesterday morning when I woke up still a bit drunk but excited about putting that jumper in and fixing this that I blew that cap off and must have hurt R5515's feelings. It must be this causing this thing to not output any display and power cycle?

So new problem before getting around to trying this new jumper cable and new NVME I have is I don't have a donor board for this model, where can I buy a replacement R5515 current sense, or how do I get a part number from the BV or schematic or is it possible to pull this part from a different model donor board?
 
2informaticos

2informaticos

Administrator
Staff member
"R5515 (current sense ) is shorting and sending continuity all over the place"
I don't understand what you've meant?
Do you have R5515 shorted to ground???
 
Anterweb

Anterweb

Member
Sorry yes it was, I've removed it now, but need to get a replacement but having trouble finding out what part to order?
 
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