Erase Disk without Screen (iMac)

Question

I have an iMac running Sierra with one SSD and one HDD where the internal screen isn't working anymore. Using it with a secondary screen works just fine.

Now I want to sell it and would like to wipe the SSD which contains the operating system. The problem I'm facing is that the recovery mode is only shown to the internal screen, on the secondary screen only the background is visible.

• I do have another mac (running Big Sur) but they do not share any connectors besides usb Type A so I cannot use Target Disk Mode.
• I cannot close the computer because it is not a laptop.
• I tried moving the window from the internal screen to the secondary screen but had no luck doing so. I'm not sure if the window is draggable.
• I would rather not open the iMac to cut any cables.

Is there any other way to wipe the disk?

Answer 1

Yes. You create a Clone with Carbon Copy Cloner on external disk, you boot on this external disk and you can erase internal disk and install a clean version of Mac os x.