How to use a 2012 MacBook Pro as an external display for a non-working 2012 iMac?

Hey there!

I'm essentially trying to export my data at this point from the iMac and call it a day. I'm having a hard time doing so.

While you cannot use target display mode, you may be able to use target disk mode:

Transfer files between two Mac computers using target disk mode - Apple Support

With a 2012 iMac and 2012 MacBook Pro, you can use a Thunderbolt (1 or 2) cable to connect the two Mac computers together. The iMac will show as an external disk on the MacBook, and you can copy files you need from it.

-Jack

thiswasmytumblr wrote:

I'm essentially trying to export my data at this point from the iMac and call it a day. I'm having a hard time doing so.

You say that you hooked up a real monitor and got no signal. If that monitor had a supported resolution (the 2012 iMacs supported resolutions of 2560x1600 pixels or less), and there was no signal, that would suggest that maybe your GPU or your motherboard had failed in such a way that the "dead" iMac won't be able to display anything on any internal or external screen.

You could try starting up the 2012 iMac in Target Disk Mode. If that works – and there's no guarantee that with a "dead" computer, it will – the 2012 MacBook Pro could pull files off of the iMac's internal hard drive, as if the 2012 MacBook Pro was an external disk drive.

Transfer files between two Mac computers using target disk mode - Apple Support

It might be possible to have a repair shop disassemble the iMac, pull the drive, and put it into an external enclosure. I believe that a 21.5" 2012 iMac would have a 2.5" notebook drive, and a 27" 2012 iMac would have a 3.5" desktop one (which would require a larger, wall-powered enclosure). But rather than going to all that trouble and expense, it would probably make more sense to restore your data from backups.

You were keeping backups, right?

You cannot use a 2012 MacBook Pro as a monitor. The only Macs which ever supported being Target Displays were certain iMacs desktop computers with hardware model years between 2009 and mid 2014. If your 2012 iMac was in working order, and you had a Thunderbolt 1/2 cable, it could have been a Target Display for your 2012 MacBook Pro. Like other MacBook Pros, your MacBook Pro never supported being a Target Display.

See: Use your iMac as a display with target display mode - Apple Support

Use the old Mac’s Time Machine backup to restore the data on it to the MacBook Pro. If you were foolish and never backed up the iMac then you can possibly connect the computers together and use Target Disk Mode (Google it) to recover data.Failing that you can take the iMac to an Apple Authorized Service Provider and ask them to remove the HD and put it in an enclosure. Then connect the enclosure to the MBP and copy the data you want.

Nope!

Please refer to Target Display Mode. Target Display Mode has been dead over 10 years now and the non-working iMac wouldn't magically come to life. All the products had to be in 100% working condition for Target Display Mode to actually work. Please recycle the non-working iMac using one of Apple's free recycling programs, you can find the one for your region by clicking Apple Recycling Programs

Please read the information in the Target Display Mode link provided. It will answer all of your questions, if it doesn't then please re-read it and you will find the answer.