Lenovo G50-30 ACLU1/ACLU2 NM-A271 rev 1.0 2013-12-05 power led on but no display

[jamesp]

hello, i need help. i have a mainboard on going repair. problem is no lcd display even connected to external monitor. all coil voltages present at the very moment i connected the charger. fan already spinning automatically. power on button board was already removed for isolation but still problem exists. power button reinstalled to confirm if it can shutdown the spinning fan, yes it can put off and on the fan and power led LED1 but still no display. if i press and hold power button it will shutdown but if i removed the charger ( board was removed from chassis. ) the power led1 will lit up and fan will spin a little and stop, still led1 on with no display on external monitor using hdmi. afterward, i try to press power button but fan will not spin and you just have to wait for sometime to see the fan will spin in eternity.

LENOVO G50-30
SNPF02FMBZ
MB: ACLU1/ACLU2 NM-A271 rev. 1.0 2013-12-05

thanks