laptop keyboard lights up and indicates its on but the screen is black

Hi,

Try a full power refresh by removing all the power from the laptop i.e. charger, main battery and RTC (Real Time Clock) battery.

The RTC battery is a coin cell battery connected to the motherboard.

So here’s the procedure:

a. Disconnect the charger if connected.

b. Remove the main battery.

c. Disconnect the RTC battery.

Here’s the ifixit Asus Rog GL55VW-DH71 Disassembly guide that shows how to get to the motherboard. You don’t have to remove the motherboard, just disassemble the laptop far enough to access the RTC battery. Maybe only as far as up to Step.4 in the guide. Be gentle and careful when working inside a laptop ;-)

Here’s an image taken from the guide that shows the location of the RTC battery

(click on image to enlarge for better viewing)

If you have a DMM (digital multimeter) use its’ Voltmeter function to test the battery’s voltage when it’s disconnected from the motherboard. If it is <2.6V DC replace it. It is a CR1220 battery I think. The model number should be printed on the battery itself. If it is <2.6V DC the BIOS can become corrupted preventing a normal start as the RTC battery maintains the BIOS settings when the laptop is switched off.

d. Press and hold the laptop’s Power button for 30 seconds and then release

e. Reconnect the RTC battery.

g. Reassemble the laptop

h. Reinsert the main battery, connect the charger and then try to turn on the laptop.

If it starts there may be a message regarding the date and time being incorrect. This is normal as the BIOS has been reset. Once it has been corrected, the message won’t appear the next time that the laptop is started.