Nearby electronic devices turn off laptop's display

Most laptops have something known as a reed switch. This is an electronic component that switches the display on or off. You display lid has a magnet, and whenever the lid comes down, the switch detects it and switches the display off to save power. It looks like this switch is detecting the magnets in your phone and speaker.

Since this issue has started recently, it probably means that your switch has gotten spoilt, or displaced. This can happen over time, especially if you dropped your laptop or knocked it against something.

Here's what you can do:

Method 1 (easy)

This way your laptop display will not switch off if you put the lid down, but other magnets won't turn it off either.

  • Click the Start (Windows) button
  • type "Power Options" and press enter
  • In the left hand pane, click "Choose what closing the lid does"
  • Under "When I close the lid:" select "Do nothing" (you can do this for on battery, plugged in, or both)
  • Click "Save Changes"

Method 2 (difficult, potentially expensive)

This way your laptop display will still switch off if you put the lid down.

  • Open your PC up or take it to a repair shop. Have them take out the reed switch or replace it with a less sensitive one.

  • If your laptop has multiple switches, you can take the one near the spacebar out.

Method 3 (for hardcore DIY enthusiasts and PC builder geeks)

Do this if the issue persists even after replacing the switch. This way your laptop display will still switch off if you put the lid down, but the phone won't do it.

  • Open your PC up

  • Use wires to extend the connections and place the reed switch elsewhere.

  • Open the lid up and place the magnet correspondingly.

My Mac does this exact thing. The lid sensor detects the lid closed when the magnetic field of a phone or of a speaker comes into contact with it, and it believes you've just closed the lid. So it does what it does when you close the lid - usually, turning off the display; potentially, putting the laptop to sleep, if you have it so configured.

The obvious answer is "don't do that".

If you want to be able to do that without the display going off, you'll have to configure it so it does not take any action when it detects the lid closed, and you'll have to manually suspend/sleep/whatever your laptop before closing the lid from then on. Most people find this too inconvenient to bother with, and just figure out a way to avoid putting magnetic fields into proximity with their laptops.