820-3115 Power rails shorted

Japtastic

New member
Is there a reference of good diode mode values for the common things like PPBUS_G3H and PP3V42_G3H for the different boards? I don't have a working spare, only donors.

I am dealing with this board and finding shorts. Both of these rails were shorted to ground, both around 32 on diode mode. I already removed U7000 and U7200 (not sure why I removed U7200 as doesn't seem relevant now) when working on this before. I gave up due to lack of confidence but feel my skills have improved a bit since last looking at it. They are still off the board.

I looked around the board for any obvious issues but didn't see anything so I injected 3.42v and found that U6400 (after a while because of foam covering) got hot. I have removed this and diode mode got me to 32 on PP3V42_G3H.

I then removed the caps and resistors associated to this circuit and have got to 160 on PP3V42_G3H.

The short on PPBUS_G3H also improved and this is now 110 diode mode.

Are these values correct with the chips I have removed? Shall I just put U7000 and U7200 back on the board now and test again?

Thanks
 
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