820-3115 ppbus low, not turning on

[BCN_Techs]

You asked me to post voltage near U7000. As i said before that there is no voltage with magsafe and i dont have false magsafe the only way is injecting Right?

 

[2informaticos]

"Change U7000 and Q7085 at same time."
Then check for voltages.
I never told you to inject voltage somewhere...

 

[BCN_Techs]

thanks, will try it tomorrow.

 

[BCN_Techs]

Sorry for delay. Changed Q7085 and U7100. Now R7085 is 740kOhms but still no green light and all rails are missing. Magsafe is getting blocked by MLB.


Well. Checked and it was Q7030 in short. No get magsafe light, PPBUS 1.9V but shorted to ground. F7040 PIN2.

 

[JohnB8812]

Your CPU has been dead from the start lol. It should not get hot on a direct short to ground unless it or a high side fet are shorter

 

[2informaticos]

If you get 1.9V, is not shorted.
Probably one high-side MOSFET shorts PPBUS_G3H to a coil of a secondary power supply.
Post exact ohm value for PPBUS_G3H and all big coils.
If problem is on CPU VCORE, you can have dead board now.

 

[BCN_Techs]

Finally sent back logic board to my customer. Too many hours with it. Thanks you all