DFU mode on a Mac: restoring or reviving firmware

Sometimes a Mac with an Apple chip no longer starts at all: no Apple logo, no startup options, not even after a failed update. Then the firmware may be damaged. With DFU mode (Device Firmware Update) you can reinstall your Mac's firmware using a second Mac. This article explains when to use DFU mode on a Mac, the difference between revive and restore, and broadly how it works.

Blue Apple repairs MacBooks in Amsterdam. If you cannot do it yourself, or have no second Mac, we can do it for you.

When do you need DFU?

• The Mac no longer responds, even after long charging and a force restart.
• A macOS update failed halfway and the Mac no longer starts.
• Startup options and Recovery mode do not work.

First try the normal steps: see opening Recovery mode and MacBook will not turn on.

Revive or restore?

• Revive: reinstalls the firmware and Recovery. Your data stays. Always try this first.
• Restore: erases everything and reinstalls firmware and macOS completely. Your data is gone afterwards. Only do this if reviving does not help and you have a backup.

What do you need?

• A second Mac with a recent macOS, with internet.
• On that Mac: Apple Configurator from the App Store (on newer macOS versions it can also be done directly via the Finder).
• A USB-C cable that carries data, not just a charging cable.

Broadly speaking

1. Connect the cable to the right port on the broken MacBook. On most MacBooks that is a specific USB-C port on the left; Apple lists which per model.
2. Put the broken MacBook in DFU mode with a special key combination: on MacBooks with an Apple chip you hold the power button together with some keys for a few seconds, following Apple's steps for your model.
3. On the second Mac the MacBook appears as a DFU device.
4. Choose Revive and wait until it finishes. The MacBook restarts.

Follow Apple's guide for the exact keys and port; a small mistake in the order means it does not work, but it does not damage anything.

It does not work

• Try another cable or the other port.
• Charge the MacBook for a while first.
• Repeat the key combination; the timing is precise.
• If the MacBook does not appear at all, there may be a hardware problem on the logic board.

Why does firmware break?

Usually because an update is interrupted: the power goes, the battery runs flat or someone turns the Mac off halfway. Sometimes because of an error during the update itself. That is why it is wise to always do big updates on the charger and not to turn the Mac off when the progress bar stands still for a while. See installing an older macOS if you want to go back after an update.

Intel Macs

Intel Macs with a T2 chip can also be put in DFU mode to restore the T2 firmware. Older Intel Macs without T2 do not have this; there you use Recovery mode or Internet Recovery. See Internet Recovery.

Your data

With revive your files stay. With restore they do not. If you have no backup and do not want to lose your data, never choose restore without advice. See MacBook data recovery.

What we do at Blue Apple in Amsterdam

We put your Mac in DFU mode, first try to revive it so your data stays, and with a hardware problem we look further at the logic board. You hear beforehand what it costs. More on our page about MacBook repair in Amsterdam.

Frequently asked questions

Can I do DFU without a second Mac?

No, you need a second Mac. If you do not have one, have a repairer do it.

Does revive erase my files?

No. Only restore erases everything.

How long does it take?

Usually a few minutes to half an hour, depending on the download.