About the SMC Firmware Updates
SMC Firmware Updates refer to the System Management Controller (SMC) firmware update for Intel-based computers. The SMC is a micro-controller on the logic board that controls the power functions for your computer. The SMC controls various functions, including:
- Power and thermal management, the Sleep LED, and battery.
- Controlling the fans, supporting Sudden Motion Sensor, ALS, and the power switch.
Tip: Print or write down these instructions before you begin installing the update.
There are three parts to this process: Determining if an update is available, installing the firmware update application and using the firmware update application to install the SMC Firmware Update.
- Determine if an update is available for your computer. See EFI and SMC firmware updates for Intel-based Macs.
- Download the SMC Firmware Update for your computer, available at Apple Downloads.
- Close any open applications.
- Double-click the SMC Update.pkg file.
- Click Continue after reading the licensing agreement then click Agree if you accept the terms.
- Click Install to install the update application.
- After the software is successfully installed, click Close to start the updater application. (If you inadvertently skipped this part, you can find the updater in /Applications/Utilities.)
- Read the onscreen firmware update installation instructions then click Restart to proceed.
As your computer starts, the SMC will be updated. Your computer's fans will run at full speed during the update but will return to normal speed once the update completes. The computer will restart again once the firmware update is complete. Important: Do not interrupt the update process.
- After your computer restarts a second time, you should see a message stating that the update was successful. Click OK to continue.
If you see the dialog that you saw in step 7 instead of a message that the update was successful, try installing the update again (use the updater in /Applications/Utilities/ ).
Note: This update requires a Macintosh-formatted disk or partition. For more information, see this article.
Some USB and FireWire devices may prevent firmware updates from installing correctly. If you are having trouble installing an update try disconnecting non-essential devices and use only an Apple keyboard, mouse, and display.