The Mac SMC reset is great. It’s basically Apple’s digital duck tape for your Mac laptop. You will need to do a SMC reset if your Mac is exhibiting these symptoms in this post list below.


  • The fans speed up and remain at high speed, even under normal usage.


  • If there is a back light, the keyboard back light does not illuminate correctly.
  • If there is a Status Indicator Light, the SIL does not illuminate correctly.
  • If there is a battery indicator light, the battery indicator does not illuminate correctly (laptops that use non-removable batteries).
  • If there is an ambient light change feature, the back light display doesn’t correctly respond to the ambient light changes.


  • The MagSafe power adapter LED doesn’t show the correct activity. (source:
  • The power button is not responsive.
  • The laptop does not respond properly when opening or closing the lid.
  • The computer sleeps or shuts down unexpectedly.
  • The battery does not appear to be charging.


  • No sound from internal speakers.
  • No audio devices in sound preferences.

Input Devices

  • USB devices stop working.

SMC Reset Instructions

Removable Battery Non-Removable Battery
  1. Shut down the mac if it’s running.
  2. Remove the battery and power adapter.
  3. Hold the power button for 10 seconds.
  4. Replace the battery and power adapter.
  5. Restart the mac.
  1. Shut down the mac if it’s running.
  2. Plug in power adapter and connect it.
  3. Press the left-side ‘Shift+Control+Option’ keys and the power button at the same time.
  4. Release all the keys and the power button at the same time.
  5. Press the power button to turn on the mac.

Additional Fixes

Another thing to try is to make sure you have updates installed.

  1. Open app store.
  2. Click Updates on toolbar.
  3. Click on update or update all for available updates.
  4. Restart laptop.

What is SMC?

The system management controller is hardware on the motherboard that controls a few core functions.

The SMC can potentially control all kinds of functions, depending on the model you’re rocking.

Update: I found a pretty good resource on this topic. To see a good list of what the SMC controls, head over to Lifewire.

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