On your another Mac, you must have Apple Configurator 2.6 installed; the secondary Mac should be running macOS High Sierra.
USB-A or USB-C to USB-C or a Thunderbolt cable
In case you are using USB-C cable, you should check that it supports power and data (you can use that USB-C cable together with a supported Thunderbolt to USB-C adapter.
In addition to above requirements, you should also configure your web proxy or firewall ports on the home router to all network traffic from Apple devices to Apple’s network 17.0.0.0/8.
Now is the time to restore a bricked iMac Pro
Step #1: Open Apple Configurator on the secondary Mac and connect the USB or Thunderbolt cable.
Step #2: Now you have to disconnect your iMac Pro from the power source; then connect the cable to iMac Pro’s Thunderbolt port, which is extremely close to Ethernet port.
Step #3: When you are holding the power button on the back of iMac Pro, connect the computer to a power source and keep holding the button for three seconds.
Here, you won’t see any screen activity from your iMac Pro.
Step #4: Next, you need to open Apple Configurator 2 on that secondary Mac.
Step #5: Select iBridge device from the app’s device browser.
Step #6: From Actions menu, select Restore.
Step #7: Then click on Restore and wait until the process is finished.
During the process to restore your iMac Pro, you may see the Apple logo appearing and disappearing.
Step #8: When the process is over, your iMac Pro should restart or reboot and you can access it again.
Step #9: Finally, you can leave Apple Configurator from the secondary Mac and disconnect the USB or Thunderbolt cable.
In case there is a power failure during the process of restoring iMac Pro, you can reboot that other Mac and start the restore process again using the above-mentioned steps.
This DFU-like restore process is required when your iMac Pro is unresponsive.
nicel patril
iMac Pro Unresponsive? How to Restore iMac Pro
Must-haves
Now is the time to restore a bricked iMac Pro
Step #1: Open Apple Configurator on the secondary Mac and connect the USB or Thunderbolt cable.
Step #2: Now you have to disconnect your iMac Pro from the power source; then connect the cable to iMac Pro’s Thunderbolt port, which is extremely close to Ethernet port.
Step #3: When you are holding the power button on the back of iMac Pro, connect the computer to a power source and keep holding the button for three seconds.
Here, you won’t see any screen activity from your iMac Pro.
Step #4: Next, you need to open Apple Configurator 2 on that secondary Mac.
Step #5: Select iBridge device from the app’s device browser.
Step #6: From Actions menu, select Restore.
Step #7: Then click on Restore and wait until the process is finished.
During the process to restore your iMac Pro, you may see the Apple logo appearing and disappearing.
Step #8: When the process is over, your iMac Pro should restart or reboot and you can access it again.
Step #9: Finally, you can leave Apple Configurator from the secondary Mac and disconnect the USB or Thunderbolt cable.
In case there is a power failure during the process of restoring iMac Pro, you can reboot that other Mac and start the restore process again using the above-mentioned steps.
This DFU-like restore process is required when your iMac Pro is unresponsive.