Why is my laptop screen very dim?

If your laptop screen is suddenly dimmer than a reality TV contestant, the solution is likely to be searingly simple or a complete pain in the hard drives. This is one of those problems with no middle ground.

First, let’s deal with the easy ones. Your laptop should have screen brightness controls somewhere on the keyboard – look for two symbols that look like suns, often on the row of F numbers at the top. You may need to press the Fn button along with the relevant icon to make the screen brighter or dimmer.

If your laptop screen is dim when you’re running on battery power, that’s what meant to happen. Windows’ power management settings reduce screen brightness to save batteries when you’re unchained from the mains, but if the screen dimming is too aggressive you can change that. Type “battery saver” into the Windows 10 search bar and open the Battery Saver Settings. In there you should find a box ticked that says “Lower screen brightness while in battery saver”. Untick that, but beware that your battery life will be shortened as a result. (Read our tips on improving battery life in Windows 10 here.)

Some fancier laptops have dynamic brightness, which use sensors to detect the level of ambient light and adjust brightness accordingly. Normally, this is a good thing, but we’ve seen it behave erratically on some models.

If you wish to turn this off, first unplug the laptop from the power adapter, and then open the Windows Control Panel (search for it if you don’t know where it lives). In Control Panel, search for Power Options, then click Change Plan Settings. On the next screen select the advanced settings option and then click the + sign next to Display. You should see an Adaptive Brightness setting here, which you can switch off.

If your screen hasn’t so much dimmed, but gone a funny yellow colour, you may have accidentally activated the night mode. This is a relatively new feature in PCs and Macs that is meant to reduce the amount of blue light belting out of your screen, which has been linked with sleeplessness. In Windows, night mode can be deactivated by clicking on the speech bubble-like icon in the bottom-right corner of the screen and selecting the Night Light icon. On a Mac, click the Apple menu, select System Preferences, select the Display icon, click on the Night Shift tab and select ‘Off’ from the schedule drop-down menu.

If the screen is very dark, almost impossible to see in a normal room, then there’s a chance the backlight has failed. That’s a problem that nobody but the most technically competent tinkerer is going to solve themselves, so it’s time for a visit to the repair shop.