A burning smell from your laptop is not good news, but it may not be fatal. Don’t panic. Quickly shut down the computer and then allow it to cool for half an hour or so. In the meantime, survey the exterior: Use your nose to isolate the source of the odor, use your fingertips (carefully) to try to find any hot spots, and use your eyes to search for anything blocking the cooling vents.

Here are some possible causes of an unpleasant electronic odor:

  • Insufficient or blocked cooling vents. If the vents appear blocked (for example, by dust or dirt), you can assume that this is the problem. Carefully clean off the vent; the best tool is a vacuum hose. Don’t use compressed air, since this will push crud into the body of the laptop.

  • A failing or overloaded AC adapter. All AC adapters generate heat. If the adapter is extremely hot, two possibilities may be causing it. First, it may be failing and need to be replaced. A second cause may be related to the voltage it is receiving from the wall outlet. Most modern adapters can work with incoming voltage ranging from 100–240 volts; that covers most every electrical standard in the world.

    The AC adapter converts the power to a level and type required by the laptop and its battery — from 12 to 24 volts. One byproduct of the conversion is heat.

  • A problem within the laptop case. If something has gone wrong within the laptop case, consult the instruction manual, Web site (on a different computer), or support desk to determine whether the laptop’s design includes a fan that runs anytime the laptop is running, or a fan that is switched on anytime the interior reaches a certain temperature.

    After the laptop has had at least half an hour to cool off, turn it back on. If the fan is supposed to come on immediately, feel for a gentle rush of air coming out of the vents; if the fan is supposed to switch on at a certain temperature, use the laptop for a while, checking for the fan. If the fan never comes on and the heat builds, you’ll have to send the laptop to a repair facility to have the fan replaced.