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820-01987 20v - 1A but no start
- Thread starter thomamagic
- Start date
First of all, welcome to the forum!
Do you get voltage at L7670/90?
Do you get voltage at L7670/90?
thomamagic
Member
thanks for your message 
L7670 : 5v
L7690 : 3.3v
L7670 : 5v
L7690 : 3.3v
Any other big coil gets voltage?
Machine should appear in DFU mode.
Be sure to follow all the tutorial steps.
You can check SOC_DFU_STATUS, to make an idea about actual board state.
Try forcing with SE032 pads.
Machine should appear in DFU mode.
Be sure to follow all the tutorial steps.
You can check SOC_DFU_STATUS, to make an idea about actual board state.
Try forcing with SE032 pads.
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thomamagic
Member
L7270 : 0v
L7210 : 0V
L7220 : 0V
L7410 : 0V
L7420 : 0V
L7702 : 0V
L8410 : 0V
L8100 : 0V
L7030 : 12.75V
SOC_DFU_STATUS is down U3900 and U3100
for dfu i don't detect
when i push the 4 button, the macbook have 20V but 0.000A
L7210 : 0V
L7220 : 0V
L7410 : 0V
L7420 : 0V
L7702 : 0V
L8410 : 0V
L8100 : 0V
L7030 : 12.75V
SOC_DFU_STATUS is down U3900 and U3100
for dfu i don't detect
when i push the 4 button, the macbook have 20V but 0.000A
thomamagic
Member
ok i have dfu mode but impossible to restore, i have error libusrestore error:21 [com.apple.MobileDevice.MobileRestore -- 0x15 (21)]
Flash SoC ROM (U4770) and try DFU again.
Make backup first.
Be aware, is 1V8 chip!
Make backup first.
Be aware, is 1V8 chip!
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thomamagic
Member
arf don't have reader for this, only for bios
can get on donor mainboard?
can get on donor mainboard?
If you plan to stay in business with MacBooks, need to get such programmer.
You can try another chip from donor board, same model.
However, should be good to make a backup of that one too.
In case you need to put it back.
You can try another chip from donor board, same model.
However, should be good to make a backup of that one too.
In case you need to put it back.
thomamagic
Member
I have buy programmer, receive tomorrow
I have lot but not for this
Thanks
I have lot but not for this
Thanks
The programmer itself is not the problem.
CH341A can do the job.
The problem is to get good 1V8 adapter and support board to solder the chip (USON 3x4).
CH341A can do the job.
The problem is to get good 1V8 adapter and support board to solder the chip (USON 3x4).
thomamagic
Member
i have receive, do you have file? or link? Thanks
A2289 T2 Unlock Data.BIN
drive.google.com
thomamagic
Member
Perfect thanks i test tomorrow when im office
thomamagic
Member
flash now and i have same error message
Error 21 was solved sometimes reflashing SoC ROM.
But may have SSD problem in fact.
Just in case, check diode mode to ground on big coils and SSD power rails.
Also check at Power FETs output, page 74.
Compare readings with good boards.
But may have SSD problem in fact.
Just in case, check diode mode to ground on big coils and SSD power rails.
Also check at Power FETs output, page 74.
Compare readings with good boards.
thomamagic
Member
what is strange is that I have no display, no ventilation and nothing on the touch bar
Why strange, if your board doesn't boot?
You can expect these untill CPU starts to work...
You can expect these untill CPU starts to work...