820-01598 reboots shortly after boot up bar starts to load.


Clean board, no history.

All SSD rails measure correct.

Tried restoring and reviving T2 but fails.

Starting from external drive not possible because we cannot change startup options in recovery mode.

I am assuming that NAND chips or one of them may be dead.


Staff member
This happened to me with 01521 board.
I finally found a shorted signal from a speaker amp to T2; it was located inside T2.
Was impossible to complete DFU on it...


Staff member
I had one with T2 shorted on SPKRAMP_RESET_L; caused by leakage from PPBUS_G3H in audio board.
That one I got it working after complete DFU,
Of course, no speaker sound, only headphones.

The one above mentioned (previous post), never complete DFU and was impossible to repair it.
T2 found shorted on a line corresponding to the other (onboard) speaker amp.
However, on other service, both boards have been connected in the same shell, with liquid damaged audio board and flex.