820-01987 No Power

thelaptoprepair

New member
Hello Everyone,
I have recently joined this forum.
I have received one A2289 (820-01987) Macbook. It shows 20 V and .079 amps on amp meter.
I already tried DFU on the macbook but failed in between. The voltage on L7030 coil is only 10 V. Please help me to resolve the issue in that case.

Thanks
 

2informaticos

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

On the new Apple boards, L7030 is not placed on PPBUS_G3H; check at F7000 instead!
Chgeck if all SSD voltages are present.
 

thelaptoprepair

New member
Thank you 2informaticos for warm welcome and quick reply.

Here are the voltages checked on U8800 chip.

F7000 12.70V
PP_SSD0_S4E2_VPP 0.013V
PP0V9_SSD0_S4E2_VDD_PLL 0.90V
PP2V5_NAND_SSD0 2.520V
PPVCCQ_ANI_SSD0 1.80V
PP1V8_IO_SSD0 1.80V
PP0V9_SSD0 0.902V
SSD0_S4E2_ANI1_VREF 0.900V
SSD0_S4E2_ANI0_VREF 0.900V
PP1V8_SSD0_S4E2_AVDD18_PLL 1.802V
PP1V8_SSD0_S4E2_PCI_AVDD_H 1.804V

The error I am getting during DFU mode :
Failed to restore device in recovery mode, libusbrestore error:21 [com.apple.MobileDevice.MobileRestore – 0x15 (21)]
Thanks
 

2informaticos

Administrator
Staff member
Any history fault available?
Did you connect the machine with correct/dedicated USB port for DFU?
Also try another cable; original Apple Thunderbolt 3 is recommended.
 
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