Lenovo Y470 notebook one common fault share

A Lenovo Y470 notebook, can not start up when connect power or using battery, The led of power adapter is flashing when connect power. Open the laptop, test the power input terminal with multimeter, there is not short circuit, then test B+ point, find short circuit, then test the mosfet PQ302, PQ302 was damaged, remove it and replace a new one. ... read more