How to revive or restore Mac firmware

Rarely, a Mac with Apple silicon or the Apple T2 Security Chip might stop responding and need to be revived or restored by another Mac.

 


When to revive or restore

If the firmware stored in its memory needs to be revived or restored, a Mac with Apple silicon or the Apple T2 Security Chip might become unresponsive. This can occur in certain rare circumstances, such as when a power failure interrupts macOS installation. Symptoms can include:

To resolve these issues without erasing any of your files, revive the firmware of your Mac. If reviving is unsuccessful, restore the firmware.

 


What you need to revive or restore

If you don't have these items or you need help, contact Apple Support.

 


How to set up your computers to revive or restore

Follow these steps based on whether the affected Mac is a laptop computer or desktop computer, and whether it's a Mac with Apple silicon or a Mac with the Apple T2 Security Chip. You will use the USB-C cable to connect the two computers, then enter DFU (device firmware update) mode on the affected Mac.

Laptop computer

  1. On the affected MacBook Pro or MacBook Air:
    • Plug the Mac into power.
    • Mac with Apple silicon: Facing the ports on the left side of the Mac, plug the USB-C cable into the leftmost USB-C port.
    • Mac with T2 chip: Facing the ports on the left side of the Mac, plug the USB-C cable into the rightmost USB-C port.

      Your port configuration might differ, but the left side of every model has a USB-C port farthest to the left (leftmost):
      Left side view of MacBook Pro showing leftmost USB-C port
      And a USB-C port farthest to the right (rightmost):
      Left side view of MacBook Pro showing rightmost USB-C port
  2. On the other Mac:
    • Plug the Mac into power.
    • Plug the other end of the USB-C cable into any USB-C port.
    • Open a window in the Finder and make sure that it shows the sidebar.
    • Make sure that the Mac is connected to the internet.*
  3. On the affected Mac, enter DFU mode:
    1. Press and hold the power button for up to 10 seconds, until the Mac turns off. (If your Mac has a Touch ID button, it's also the power button.)
    2. Press and release the power button, then immediately press and hold all four of these together on the built-in keyboard:
      • Power button
      • Shift ⇧ on the right side of the keyboard
      • Option ⌥ on the left side of the keyboard
      • Control ⌃ on the left side of the keyboardTop view of MacBook Pro keyboard, showing the four keys to press and hold
      • Mac with Apple silicon: Keep holding all four keys for about 10 seconds, then release all keys except the power button. After about 3 seconds, release the power button.
      • Mac with T2 chip: Keep holding all four keys for about 3 seconds, then release all keys.
  4. Follow the steps to revive or restore

Desktop computer

  1. On the affected desktop computer:
    • iMac: Facing the back of the Mac, plug the USB-C cable into the rightmost USB-C port.
    • Mac mini with Apple silicon: Facing the back of the Mac, plug the USB-C cable into the leftmost USB-C port.
    • Mac mini with T2 chip: Facing the back of the Mac, plug the USB-C cable into the rightmost USB-C port.
    • Mac Studio: Facing the back of the Mac, plug the USB-C cable into the rightmost USB-C port.
    • Mac Pro with desktop enclosure: On the top of the Mac, plug the USB-C cable into the USB-C port farthest from the power button. 
    • Mac Pro with rack enclosure: On the front of the Mac, plug the USB-C cable into the USB-C port closest to the power button.
  2. On the other Mac:
    • Plug the other end of the USB-C cable into any USB-C port.
    • Open a window in the Finder and make sure that it shows the sidebar.
    • Make sure that the Mac is connected to the internet.*
  3. On the affected Mac, enter DFU mode:
    1. Unplug the Mac from power.
    2. Press and hold the power button.
    3. Keep holding the power button while plugging the Mac into power.
    4. After about 3 seconds, release the power button. 
  4. Follow the steps to revive or restore

 


How to revive or restore

After setting up your computers, follow these steps to revive or restore the affected Mac. Until that process is underway, the display of the affected Mac remains blank.

Finder window showing the Revive Mac and Restore Mac buttons

Revive

Try reviving first. It's faster than restoring, and it doesn't erase your Mac.

  1. In the sidebar of the Finder window, select “Mac,” which is the Mac you're reviving. Don't see it?
  2. Click Revive Mac on the right, then click Continue to confirm. A progress bar in this window shows that the revive is underway.
  3. Disconnect the revived Mac when asked. It then restarts automatically.
  4. If asked, select a user you know the password for, and enter that user's password. Click Next, then click Restart.
  5. Mac with Apple silicon: The revived Mac loads startup options, which includes Options with a gear icon. Select your startup disk (Macintosh HD), then click the Continue button that appears below it.
  6. The revived Mac finishes starting up and the process is complete. 

Restore, if necessary

If your Mac can't be revived, follow these steps to erase it and restore it to factory settings. 

  1. Set up the affected Mac and make sure that it's in DFU mode. 
  2. In the sidebar of the Finder window, select “Mac,” which is the Mac you're restoring. 
  3. Click Restore Mac on the right, then click Restore and Update to confirm. A progress bar in this window shows that the restore is underway.
  4. Disconnect the restored Mac when asked. If it shuts down instead of restarting, press the power button to turn it on.
  5. If asked, select a Wi-Fi network or attach a network cable.
  6. Mac with Apple silicon: 
    1. If asked, enter the Apple ID and password that was previously used with this Mac.
    2. When the Mac setup assistant opens, use it to finish setting up your Mac. 
  7. Mac with T2 chip: 
    1. The restored Mac shows a spinning globe as it starts up from macOS Recovery over the internet. 
    2. Choose your language when asked.
    3. If asked, enter the Apple ID and password that was previously used with this Mac. Then click Exit to Recovery.
    4. When you see the list of utilities in Recovery, choose the option to install or reinstall macOS
    5. After macOS installation, the Mac restarts and opens the setup assistant. Use it to finish setting up your Mac.

 


If you don't see "Mac" in the sidebar

After setting up your computers, if the affected Mac doesn't appear in the sidebar of the Finder window:

  • From the menu bar in the Finder, choose Finder > Settings. Click Sidebar at the top of the settings window, then make sure that “CDs, DVDs, and iOS Devices” is selected. 
  • Press and hold the power button for up to 10 seconds to turn off the affected Mac. Then make sure that the USB-C cable is plugged into the correct port, and try again to enter DFU mode. Proper timing of key and button presses is important.

If you still need help, please contact Apple Support.

 


Learn more

You can also download and use Apple Configurator to revive or restore firmware. This method has the same setup requirements, but your other Mac doesn't need to be using macOS Sonoma or later.

Reviving or restoring firmware is not the same as installing the firmware updates included with macOS updates.

 

* If you're using a web proxy or firewall, it must allow network traffic from your Mac to Apple’s network, 17.0.0.0/8. If you're not sure, consult your router manual or internet provider. Learn more about using Apple products on enterprise networks.

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