820-01987 No Power

[2informaticos]

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]

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]

Do you get the same message error in revive and restore?

 

[thelaptoprepair]

Yes, I was getting the same error. Please suggest me any solution for this problem.
Thanks

 

[2informaticos]

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.

 

[thelaptoprepair]

Okay, Thanks for suggestions. I will try and update the results.
Thanks