Power supply -> OK 19V
no apparent sign of hot component . The motherboard is on and off . Tested the transistor mosfet PQ3 near the source connector and is not shorted. Not found the schematic diagram of the motherboard on the internet. Removed all the internal peripherals Notebook leaving only the processor, memory and cooler.Without any video signal

I checked the resistance on the mosfet transistor PQ30 and PQ32 and accuses 0.06 ohms. value measured without the processor

The motherboard connects and after + / - 5 sec off to return the call again

measured voltages on the PU2:

pin 16 --> 19v
pin 13 --> 2.42v
pin 23 --> 3.27 dropping to 0v returning to 3.27
pin 1 --> 1.13 dropping to 0v returning to 1.13
pin 6 --> 1.13 dropping to 0v returning to 1.13
pin 18 --> 3.3v
pin 3 --> 1.95v
pin 8 --> 3.30v
pin 17 --> 5v

Schematic: