820-01041 20v 0.06a and unable to restore T2

No-Clean

Member
Clean board, someone already tried to mess with it and U7000 looked like it was removed the put back, clean other than that.

Restoring in both Catalina and Big Sur give same error, the software hangs for ever and cannot restore T2

Measuring NAND voltages the only weird measurement is P0V9_LX0_SSD1 at 0.6V while P0V9_LX0_SSD0 is fine at 0.9V, PP1V8_SSD0 and PP1V8_SSD1 are fine at 1.8V and PP2V5_NAND_SSD0 and PP2V5_NAND_SSD1 is fine at 2.5V.
 

2informaticos

Administrator
Staff member
If machine is detected in DFU, but cannot complete the process, very likely SSD problem.
More than probable in your case, as you already have a bad SSD voltage.
Of course, can be T2 itself with internal damage.
 

No-Clean

Member
This may be a silly thing to say, but can that side of the SSD on the board be disable so it only uses either 256Gb or 512Gb instead of 1Tb? The problem on this board is with P0V9_LX0_SSD1 while P0V9_LX0_SSD0 is fine.
 

No-Clean

Member
Okay if I inject 0.9V from the PS into P0V9_LX0_SSD1 the computer boots up and works, any tips on how to take this voltage from somewhere else on the board to make it a permanent solution will be greatly appreciated, I tried a few dumb options but had no luck.
 

2informaticos

Administrator
Staff member
You should change U9500.
I don't think to be a good idea to pick PP0V9_SSD0 from U9000 side (leaving out L9520/21); overload may kill it.

You can try with a small buck converter to get it from 3V3_G3H_SSD1.
You may need to find one to work with 3V3 input; the above one accept 4.5V, is just an example.
 

No-Clean

Member
Thanks, I just ordered the chips from China, I hope with just the chip the MacBook will work, otherwise I have looked at the step down converter and the closest one I found is this one the only problem is that the minimum input is 4.5V the output can be adjusted, will it work you think?
 
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