I received this laptop, no history and the motherboard was in short circuit on main power rail. Then i noticed that motherboard literaly burned in one part...near the capacitors PC85 and PC86...there were almost 5 mm burned part of the board 
That part and capacitors are on PWR_SRC_FBVDDQ rail...and that is main rail powering FBVDDQ mosfets. It was shorted to gnd. Then i cleaned everything, cut all that was burned and with microscope inspection couldnt find any part touching or burned. The resistence is now only 58 ohms relative to GND and that is not good for main power rail. Then i removed U30, U24, U23, PQ25,PQ23, PEC12,PEC10 and PC134 and on PWR_SRC_FBVDDQ i have resistence 58 ohms relative to GND and on all other main power rails readings are in killoohms.
So, i checked with multimeter is there a short between PWR_SRC_FBVDDQ power rail and any other on the board but there is not...it is just showing 58 ohm resistence to ground but it seems it is not conected to any other rail on the motherboard (with above mentioned smd components removed).
So i dont get it? maybe it is still touching somewhere something..but then i would have multimeter beep?
Have anyone else repaired burned motherboards or/and have any other idea?
I attached boardview.

That part and capacitors are on PWR_SRC_FBVDDQ rail...and that is main rail powering FBVDDQ mosfets. It was shorted to gnd. Then i cleaned everything, cut all that was burned and with microscope inspection couldnt find any part touching or burned. The resistence is now only 58 ohms relative to GND and that is not good for main power rail. Then i removed U30, U24, U23, PQ25,PQ23, PEC12,PEC10 and PC134 and on PWR_SRC_FBVDDQ i have resistence 58 ohms relative to GND and on all other main power rails readings are in killoohms.
So, i checked with multimeter is there a short between PWR_SRC_FBVDDQ power rail and any other on the board but there is not...it is just showing 58 ohm resistence to ground but it seems it is not conected to any other rail on the motherboard (with above mentioned smd components removed).
So i dont get it? maybe it is still touching somewhere something..but then i would have multimeter beep?
Have anyone else repaired burned motherboards or/and have any other idea?
I attached boardview.
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