Hi,
I have a Samsung 860 Evo 1TB SATA drive (model MZ7LH1T0HMLU) which is not seen by the BIOS. I was hot plugging some test HDDs to an eSata connector, and while doing a read test on another drive, the Samsung went offline. No damage was done to the other drive, but the 860 Evo does not appear now at all. The usual diagnosis steps (try different cable, try different PC, etc) did not help. Drive is not recognized in anything.
Upon disassembling, I saw a board marked as MZ7LH1T0HML0. The layout is very close if not the same as every other teardown you can see online - for ex.
https://tpucdn.com/ssd-specs/images/d/12-pcb-front.jpg. Visual inspection of the components did not show any damage.
With the power off, I measured all the SMD capacitors and none of them looked shorted (none had continuity between the two ends, all measured to have some resistance).
With power on (using a usb2.0 to SATA external connector I had at hand), I was reluctant to do much measurements due to how small the components are. One important thing that stood out was two components getting hot: one was the DRAM chip, which got very warm to the touch, but I suppose this is normal. The other was the e-fuse right next to the DRAM (small rectangular 10-pin chip) which was BURNING hot and I could not touch it for more than a second. Due to the extreme heat given off by the e-fuse, I'm thinking that it is the culprit.
I read in another thread that it is possible to just bridge the voltage input and output pins of the e-fuse to get the drive working "with some caveats", if this works the first thing I'd do is a full backup, so if it can give 2-3 more hours of life to the drive, that would be all I need.
So, my questions are:
- what else can and should I do to get a more accurate diagnosis?
- could there be something else broken, or is it most likely the e-fuse? I did not measure any shorts on any of the caps.
- if it is the e-fuse, should I remove it before bridging the Vin and Vout pins, or can I leave it in place and bridge it that way? Obviously I'd route the bridge cable so it goes around the chip, to avoid the heat.
My last backup of this drive is over a year old (yes, I'm stupid), so I'd really like it if it was possible to restore the data. It's not terribly important data, but restoring it would be very annoying and take a while.
Attached pics of the board serial and the e-fuse, they are crappy phone pics, I'll make some proper pics soon.