Therefore, try unplugging the unit both from the wall and from your computer, and setting it in a cool place for about 5-10 minutes to see if it works again. When these features are triggered they may require time to reset and allow the adapter to work again. These spikes may trigger the adapter's over-voltage protection circuits which, similar to the temperature sensor, will shut off the adapter to prevent damage to the component circuitry. In addition to heating, some wall circuits might have excessive line noise (voltage spikes and drop-outs) that occur too often for the adapter to manage. It's not uncommon for adapters to be put in poorly ventilated areas or to get shoved between the cushions of a couch or chair that insulates them and causes them to rapidly heat up. Apple's adapters can get quite hot and do have a temperature sensor in them that will shut it off if it overheats. If your adapter isn't working, the first thing you should do is unplug it for a while. While often the easiest solution for a faulty power adapter is to replace it with a new one, before doing this there are some steps you can take that will ideally address the problem. Sometimes they get very hot when used, or sometimes they won't charge the system or show any activity at all.
Depending on your system, you may have a 60-watt adapter or an 85-watt adapter, which can be used to charge the system or run it directly from wall power however, there are times when these adapters might not work properly. If you own one of Apple's MacBook, MacBook Pro, or MacBook Air systems, you will have a power adapter that comes with the unit for charging it.