820-2879-b

Haralampos

New member
I have this board for repair with water damage. All cleaned and the ugly parts exchanged. Now i get the following components very hot when i put 3 volts on them :

C2901
C3101

C2300

as well as the RAM blocks.

Any suggestions? PP3V42 ist present and stable, i have green light as well. F7040 is shorted on PIN2, that where i put 3V on the board.
 

dukefawks

Administrator
Sounds to me like a shorted high side FET on the memory power bus Q7330. I'm afraid that will have done terminal damage to MCP/RAM and more.
 

Haralampos

New member
it is absolutely shorted, i recognized it by burning my finger.

Where can i find the specs to this part?
I would like to change and give it a try.
 

dukefawks

Administrator
This board is toast....waste of time.
But if you must, U7300, Q7330, Q7335 should all be changed together. Source from scrap board...Any board that has a TPS51116 on it, you can then also take the FETs if they are the same size. Exact part numbers are not critical on the FETs.
Actually measure resistance to GND on the 3V42_G3H bus, anything under 17K will also be a dead MCP89 and also make it instant death.
 
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