Repair or restore macOS firmware in DFU mode on Apple silicon Macs

Fresh install of macOS Ventura in DFU mode on Apple-powered Macs

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Mac computers with Apple silicon, referred to as Apple silicon Mac, translates into Chinese as "Mac computers equipped with Apple chips".

2023.06.13 Update, adding new models: new 15-inch MacBook Air, Mac Studio, and Mac Pro with Apple chips (available on June 13, 2023).

2023.02.07 update, adding new models MacBook Pro (14, 16 inches, M2 Pro/M2 Max, 2023) and Mac mini (M2/M2 Pro 2023).

2022.08.17 Update: Added new models Mac Studio (2022), MacBook Pro (13-inch, M2, 2022), and MacBook Air (M2, 2022).

2021.11.28 Update: Added new models 2021 14-inch or 16-inch MacBook Pro with Apple Silicon.

2021.05.25 Update: Added new model iMac (24-inch, M1, 2021) related content.

This article was originally written based on the Mac equipped with the Apple M1 chip in 2020. The relevant features of the new version of the hardware may change. Please correct me if there is any inappropriateness, thank you.

1. Understand the new features of Apple silicon Mac in the system and firmware

Macs with Apple chips have certain system and firmware changes compared to Macs based on Intel processors.

1. Understanding Apple silicon Mac models

This task applies to the following Mac computers with Apple Silicon:

Starting with some models introduced in late 2020, Apple started the transition of Mac computers from Intel processors to Apple chips. June 2023 The new 15-inch MacBook Air, Mac Studio and Mac Pro with Apple silicon are now available. With the Mac Pro featuring the M2 Ultra chip, the transition of the Mac lineup to Apple silicon is complete.

Mac computers with an Apple chip:

• MacBook Pro introduced in 2021 or later , and MacBook Pro (13-inch, M1, 2020)
• MacBook Air introduced in 2022 or later , and MacBook Air (M1, 2020)
• iMac launching in 2021 or later
• Mac mini introduced in 2020 or later
• Mac Studio
• Mac Pro launching in 2023 or later

On Mac computers with an Apple chip, About This Mac displays an item labeled "Chip" followed by the name of the chip:

To open About This Mac, choose Apple menu  > About This Mac.

On Mac computers with Intel processors, About This Mac displays an item labeled "Processor" followed by the name of the Intel processor. A Mac with an Intel processor is also called an Intel-based Mac.

See also: Mac computers with Apple chips

2. The startup method of macOS Recovery is different

• Apple Silicon : Turn on your Mac and continue to hold the power button until you see the boot options window (sysin), which contains a gear icon labeled "Options." Select Options, then click Continue.
• Intel processors : Make sure your Mac is connected to the Internet. Then, turn on your Mac and immediately hold down Command (⌘) + R until you see the Apple logo or other image.

Apple silicon Mac Boot Manager

3. Apple silicon System Recovery (new feature)

Apple silicon System Recovery is a new hidden recovery option in addition to macOS Recovery. If for some reason macOS Recovery becomes corrupted, System recovery will load (sysin) the same way as macOS Recovery. You can use it to reinstall macOS and macOS Recovery.

If both macOS and System Revovery are broken: If your Mac starts up with an exclamation point in a circle

4. Internet Recovery is obsolete

Compared:

• Apple chip : does not exist

• Intel processor :

  Option-Command-R: Boot from macOS Recovery over the Internet. Use this key combination to reinstall macOS and upgrade to the latest version of macOS compatible with your Mac.

  Option-Shift-Command-R: Boot from macOS Recovery over the Internet. Use this key combination to reinstall the version of macOS that came with your Mac, or the closest version still available.

5. Mac Sharing Mode replaces Target Disk Mode

Note: It is recommended to use a Thunderbolt 3 or Thunderbolt 4 cable, otherwise the speed will be worrying (sysin).

• Apple chip : Long press the power button to enter "Options" > Enter Recovery Mode > Menu "Utilities" > "Shared Disk".

  Link: Transfer files between an Apple Silicon Mac and another Mac

  1. Connect the two computers with a USB, USB-C or Thunderbolt cable.

  2. On Macs with Apple Silicon, choose Apple menu  > Shut Down.

  3. Press and hold the power button until Loading Boot Options appears.

  4. Click Options, then click Continue.

     If requested, enter the password for the administrator account.

     Your Mac will turn on in recovery mode.

  5. Choose Utilities > Shared Disk.

  6. Select the disk or volume to share, then click Start Sharing.

  7. On the other Mac, open a Finder window, then click Network in the sidebar (under Places).

  8. In the Network window, double-click the Mac with the shared disk or volume, click Connect as, select Guest in the Connect as window, then click Connect.

  9. Transfer files.

  10. After the file transfer is complete, eject the disk on the other Mac.

• Intel processors : Press and hold the Power key and the T key simultaneously.

  Link: Transfer Files Between Two Mac Computers Using Target Disk Mode

  1. Connect the two computers with a FireWire or Thunderbolt cable.

  2. On the Mac you want to use as a disk in Target Disk mode, do one of the following:

     • If the computer is off, start it while holding down the T key.
     • If your computer is turned on, choose Apple menu  > System Preferences, click Startup Disk, then click Target Disk Mode.

     When the computer starts up, a disk icon appears on the other computer's desktop.

  3. You can drag files to and from the disk to transfer them.

  4. Drag the disk icon to the Trash to eject it.

     As you drag, the trash can icon changes to an Eject icon.

  5. On a Mac used as a disk, press the power button to turn it off, then disconnect the cable.

6. Safe Mode (starting in a different way)

The operation method is as follows (sysin):

• Start an Intel-equipped Mac in Safe Mode

  1. On a Mac, choose Apple menu  > Shut Down.

     After your Mac shuts down, wait 10 seconds.

  2. Restart your Mac, then immediately hold down the Shift key.

  3. Release the Shift key when you see the login window.

• Start an Apple Silicon Mac in Safe Mode

  1. On a Mac, choose Apple menu  > Shut Down.

     After your Mac shuts down, wait 10 seconds.

  2. Press and hold the power button until the startup disk and Options appear.

  3. Hold down the Shift key, then click Continue in Safe Mode.

7. Apple silicon Mac "External Boot" is enabled by default

see:

• Apple Silicon : Change security settings on Macs with Apple Silicon .
• Intel Processors : Open the Boot Security Utility

8. macOS ipsw package

That's right, like iOS, Apple silicon Macs can be restored and updated (via Apple Configurator 2) via ipsw files for firmware.

9. DFU mode

The full name of DFU is Device Firmware Upgrade, which is the forced downgrade mode of iOS firmware. Apple silicon Macs can also boot into DFU mode.

How to boot into DFU mode is described below in "Step 2: Prepare the target Mac" (sysin).

10. Can the system version be downgraded?

The macOS version for Apple silicon Macs can still be downgraded.

"Full Security" is enabled by default (equivalent to iOS), and security policy needs to be set to "Downgrade Security", see: Change startup disk security settings on Macs with Apple Silicon .

For comparison see: About the Startup Security Utility on Macs with the Apple T2 Security Chip

11. Understand how Apple silicon Mac restores the system

Compared with Intel-based Mac computers equipped with Apple T2 security chips, Macs equipped with Apple chips lack Internet Recovery, and other recovery methods are similar, but you can manually download ipsw for repair or recovery, so that you can specify the version.

• 1. macOS Recovery

• 2. System Recovery – (will start automatically if macOS Recovery is not available)

• 3. macOS Big Sur USB boot install – (" External boot " is enabled by default, the operation method has not changed, except for the key to boot the installer)
  • Intel processors: Hold down the Option (Alt) ⌥ key immediately after turning on or restarting your Mac . Release the Option key when the black screen for bootable volumes appears.
  • Apple Silicon: Turn on your Mac and continue to hold the power button until you see the Startup Options window, which displays Bootable Volumes.

• 4. Apple Configurator 2 REVIVE option – will repair the firmware and reinstall macOS Recovery (update the firmware and update recoveryOS to the latest version), user data remains in the SSD

• 5. Apple Configurator 2 RESTORE option – will reinstall macOS Recovery, will erase the entire disk to reinstall macOS, and of course user data will also be erased

This article describes the use of Apple Configurator 2 to restore the system.

2. Preparation and Requirements

1. An additional Mac, what we'll call the "primary Mac" (sysin) here, with a Type-C port, Intel processors and Apple chips will do.

2. System version macOS Catalina 10.15.6 and above (the latest version is recommended).

3. Download Apple Configurator 2 .

4. Download the macOS ipsw format software.

   • macOS Big Sur
   • macOS Monterey
   • macOS is coming

   Apple Configurator 2 will automatically download the latest version of ipsw firmware (similar to iOS). It is recommended to manually download it to the local (you can specify the version), and drag it directly to Apple Configurator 2 for recovery.

5. USB-C to USB-C Cable : A supported USB-C to USB-C charging cable, such as those sold by Apple . A Thunderbolt cable is even better.

6. Cable connection: "Main Mac" can be any C port, and the target Mac (the Mac to be restored) must be a designated C port (see the description below for details).

7. Make sure the "Primary Mac" is plugged in or has sufficient battery power, and an active internet connection.

3. Repair or restore Macs with Apple silicon

Step 1: Connect the USB-C cable and open Apple Configurator 2 on the "Primary Mac"

The steps are as follows:

• Make sure your "main Mac" is plugged in and powered on, connect the Type-C cable (any port).
• Shut down the target Mac (the one being restored).
• Plug the USB-C cable into the designated C port of the target Mac (the Mac to be restored). Described below respectively.
• Launch Apple Configurator 2 on the "Primary Mac".
  

Insert the USB-C cable into the designated C port of the target Mac (the Mac to be restored), as follows:

(1) Mac Pro

For a desktop Mac Pro, plug the USB-C cable into the Thunderbolt port furthest from the power button.

For rack-mounting your Mac Pro, plug the USB-C cable into the Thunderbolt port closest to the power button.

(2) MacBook Pro (14 inch/16 inch, 2021 2023)

Left side of a 14-inch or 16-inch MacBook Pro with an Apple Silicon, showing the rear two Thunderbolt 4 (USB-C) ports, with the leftmost port highlighted.

(3) Mac mini

Mac mini 2023 with the M2 Pro chip, showing an expanded view of the four Thunderbolt 3 or 4 (USB-C) ports, with the leftmost port highlighted.

The back of a Mac mini with Apple Silicon showing an expanded view of the two Thunderbolt 3 or 4 (USB-C) ports, with the leftmost port highlighted.

(4) MacBook Air (M2, 2022 2023)

Left side of MacBook Air (M2, 2022), showing the two rear Thunderbolt 3 (USB-C) ports, with the leftmost port labeled.

(5) Mac Studio

The back of the Mac Studio (2022, 2023), showing the four rear Thunderbolt 4 (USB-C) ports, with the rightmost port labeled.

(6) iMac

Back of iMac (24-inch, M1, 2021), showing the two rear Thunderbolt 3 (USB-C) ports, with the rightmost port labeled.

Back of iMac (24-inch, M1, 2021), showing the four rear Thunderbolt 3 (USB-C) ports, with the rightmost port labeled.

(7) MacBook Pro (13-inch 2020 2022)

Left side of MacBook Pro (13-inch) with Apple Silicon showing the two rear Thunderbolt 4 (USB-C) ports, with the leftmost port labeled.

(8) MacBook Air (M1, 2020)

The image shows that users should select the port closest to the left display of a MacBook Air with an Apple chip.

Step 2: Prepare the target Mac (restored Mac)

(1) Prepare iMac (24-inch, M1, 2021) (enter DFU mode)

1. Press the power button.

2. While holding down the power button, press all three of the following keys for approximately 10 seconds:

   • Right Shift key
   • Left Option key
   • Left Control key

3. After 10 seconds, immediately release the three keys but continue to hold the power button until the DFU icon appears in Apple Configurator 2.

   Note: There will be no screen activity on the iMac (24-inch, M1, 2021) that you are repairing or restoring.

(2) Prepare Mac mini or Mac Studio (enter DFU mode)

1. Plug in a monitor to see when the restore process is complete.

2. Unplug your Mac mini from power for at least 10 seconds.

3. Press and hold the power button.

4. Reconnect the power supply while holding down the power button.

5. Release the power button.

   The status light should be amber.

   *[Note]* There will be no screen activity on the Mac mini.

(3) Prepare MacBook Air or Macbook Pro (enter DFU mode)

1. Press the power button.

2. While holding down the power button, press all three of the following keys for approximately 10 seconds:

   • Right Shift key
   • Left Option key
   • Left Control key

3. After 10 seconds, immediately release the three keys but continue to hold the power button until the device appears in Apple Configurator 2.

   Note: There will be no screen activity on the MacBook Air or MacBook Pro that you are trying to repair or restore. If the MacBook Pro uses the MagSafe connector, there is no LED charge indicator.

(4) Verification status

As it turns out, getting an Apple silicon Mac into DFU mode isn't that easy. It is often necessary to try several times according to Apple's description. If you cannot enter DFU mode, you need to start again. Please refer to the following points:

1. The target Mac must be powered off to start.
2. Simultaneously press and hold the Power key , Right Shift key , Left Control key and Left Option key for 10 seconds (watch the screen counting when you open Apple Configurator 2, you can let the computer display the seconds) and then release all keys (sysin) except the Power key. Continue to hold the power button for 8 seconds for a total of 18 seconds. If the count exceeds 20 seconds and you do not see the DFU icon, you will need to retry the process.
3. When the target Mac properly boots into DFU mode, a large DFU icon appears in Apple Configurator 2 (pictured below). You can release the power button at this point.

The Apple Configurator 2 status changes on the "Primary Mac" are as follows:

(1) The target Mac has not booted into DFU mode, as shown below:

(2) The target Mac has been correctly booted into DFU mode

(3) The target Mac cable is connected correctly, and the recovery mode selection window has been booted (for reference only, it is not necessary to boot into this mode here)

(5) How to exit DFU mode

The method described here is to exit DFU mode, and this operation step is not required. After the operation is successful, it will automatically exit the DFU mode.

• Right-click on the DFU icon, select "Advanced" from the menu, and select "Restart Device" or "Shut Down Device"

  

• If the above operations do not work, press and hold the power button (more than 4 seconds) to shut down the device and exit DFU mode.

• After the recovery operation is successful, it will automatically exit DFU mode.

Step 3: Drag and drop the ipsw file to the DFU screen to restore

Please drag the downloaded macOS ipsw file onto the DFU icon to start the recovery.

After dragging the macOS ipsw file, a prompt box will pop up, select "Restore" to erase the disk and reinstall macOS. The whole process takes about 15 minutes.

A prompt screen will pop up, select "Restore" to restore to factory settings. (Of course you can also click "Repair" to keep all content and settings)

If you don't have ipsw downloaded (or don't know where to download ipsw manually), go directly to "Alternate Step 3" below

Alternative step 3: Repair or restore firmware (no need to prepare ipsw, automatic network download)

This method has high requirements on the network. In addition, the latest version is downloaded, and the version cannot be specified, so it is not recommended.

Option 1: Repair (Revive) the firmware and install the latest recoveryOS

1. In the Devices window of Apple Configurator 2, select the Mac whose chip firmware you want to repair and update its recoveryOS to the latest version.

   

2. Do one of the following:

   • Choose Actions > Advanced > Repair Device, then click Repair.

   • Control-click the selected device and choose Advanced > Repair Device, then click Repair.

     Note: If any Mac dies during the process, start the repair process again.

3. Wait for the process to complete. During this process, the Apple logo will appear and disappear.

4. After the repair process is complete, your Mac will restart.

   【Important】 When repairing the firmware, you must confirm that it has been successfully repaired, because Apple Configurator 2 may not remind you.

5. Quit Apple Configurator 2, then unplug any adapters and cables.

Option 2: Restore the firmware, erase all data and reinstall the latest versions of recoveryOS and macOS

1. In the Devices window of Apple Configurator 2, select the Mac you want to restore.

2. Do one of the following:

   • Choose Actions > Restore, then click Restore.

     

   • Control-click the selected device and choose Actions > Restore, then click Restore.

     Note: If any Mac dies during the process, start the restore process again.

   

3. Wait for the process to complete. During this process, the Apple logo will appear and disappear.

4. After the restore process is complete, your Mac restarts.

   【Important】 When restoring your Mac, you must confirm that the restoration was successful, because Apple Configurator 2 may not remind you.

5. If the restore was successful, the macOS Setup Assistant will be displayed.

6. Quit Apple Configurator 2 and unplug any adapters and cables.

4. Digression: Comparing and repairing Intel-based Macs

Use Apple Configurator to fix or restore differences for Intel-based Macs :

• The target Mac uses the USB-C on the right (Apple Silicon Mac notebooks use the left port, and desktops use the right port).
• By default there is only "Repair" option, which will update the firmware (T2 chip firmware) to the latest version (but there is one exception as follows).
• Mac Pro only (2019): Restore the firmware, erase all data, and reinstall the latest versions of recoveryOS and macOS.

The table below lists the differences (sysin) for repairing or restoring iOS and derivatives devices and Mac.

equipment	repair	recover
iPhone and iPod touch	User data may be preserved (if recoverable).	Erase user data. Erase and reinstall the latest version of iOS.
iPad	User data may be preserved (if recoverable).	Erase user data. Erase and reinstall the latest version of iPadOS.
Apple TV	User data may be preserved (if recoverable).	Erase user data. Erase and reinstall the latest version of Apple's tvOS.
Macs with Apple Silicon	Update sepOS and recoveryOS to the latest publicly released versions. User data may be preserved (if recoverable).	Erase user data. Erase and reinstall the latest publicly available versions of sepOS, recoveryOS, and macOS.
Intel-based Macs with the Apple T2 Security Chip	Only update the T2 chip firmware. User data may be preserved (if recoverable).	Erase user data. Erase and reinstall the T2 chip firmware only. Both recoveryOS and macOS must be reinstalled using Internet Recovery.

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