A1989 820-00850 - Hole on UB300, after replacement, UB400 loops 5V 0.27A

it-solve

Member
T2 gets warm, PMU voltages are present

Replaced both UB3/400 multiple times.
Device is visible in DFU via U31/3200.

Does it seems like CD32 issues?
Was it CD3215 which needs all 4 to be alive or only 2 on one side?
 

it-solve

Member
I swapped Rom from same donor board i know is working. Would that ROM need any work on?

both side CD32s now stay at 5V 0.06A, t2 warms up
left side is still visible in DFU

This ROM on donor Macbook pushes it straight to DFU. Donor boots with original ROM.

With that donor ROM also its original, half way through DFU revive, Installing system hangs and DFU disconnects.
 
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it-solve

Member
OK I managed to charge the battery with donor board and now it turned on. This with original ROm
However it is not charging on any ports. USBcs are working however as i can transfer the data.


With battery connected left USBcs stays at 5V 0.24A
Top Right USBs - 5V 0A
Bottom right USBc - no power

With disconnecte battery all usbc stays at 5V 0.25A
 
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it-solve

Member
Swapped UB090 from working board, still not transitioning to 20 without battery. Stuck at 5V 0.27A and cycles to 0A on the right ports every 10s

Replaced UB300 again, also replaced QB300 as seems like there was sticky corrosion underneath.
 
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