Lenovo Y540 randomly turns the screen off.

Hi,

Things to try:

Try connecting an external monitor (TV?) to the laptop’s HDMI port and check if its display goes black as well? Here’s the user manual. Go to p.18 & p.19 to see how to do this.

If the external monitor screens stays on, when the laptop’s screen goes black, try shining a torch at an angle close to the laptop screen and check if you can detect any images at all. They will be very faint so trying this in a darkened room may help to see them.

If you can detect images then there is a backlight problem with the display. Either in the display or the backlight power circuit to the display.

If the external monitor screen also goes black try getting into BIOS on startup and check if the laptop display stays on or not.

If it stays on then there may be a video driver problem. Have you checked that the video drivers are up to date?

If it also goes black it may be a GPU problem. Have you checked that both fans are working and that the air vents are clear and unobstructed? If necessary here’s the hardware maintenance manual for the laptop. Go to p.40 to view the necessary pre-requisite steps and then the procedure to remove the fans.