I have an older iMac was looking to use as a target mode monitor. It won't boot up, just keeps restarting. I was able to wipe the HD and reinstall the OS but still won't reboot. Also took the ram out and tried different combinations of ram. Any ideas on anything else to try to get it to start up?
I can get it into the macOS Utilities with Command-R.
I looked through a lot of other threads and did not see anything else to try.
Thanks,
Michael Howard
See if you can boot into Safe Mode by booting with the Shift key held down. If successful reboot normally.
NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following;
• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files
See if you can boot into Safe Mode by booting with the Shift key held down. If successful reboot normally.
NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following;
• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files
While in the Recovery Partition please open Disk Utility and then run First Aide 3-4 times back to back and look for any errors. I suspect the HD has crashed. If the computer is older than a 2014 model, then I'd seriously consider replacing it.
You can also use the information in If your Mac won't turn on or start up. If none of those work or if you get ANY errors in First Aide that just confirms my thoughts about the HD.
Good luck.
I was able to finally get it to boot using Guest. I also was able to use it as a monitor from my MacBook. I just don't know how stable it is. Was an interesting exercise anyway. Thanks for everyone's input.
Unless the 2011 is 100% functional Target Display Mode will not work. Also, what Mac are you attempting to connect to, we need the year and version of Mac OS installed on that machine.
What year model is the older iMac?
Only certain year models worked as displays in Target Display Mode, Plus if you have a new Mac, it can not use an older iMac as a display in Target Display Mode.
for mode details, see > https://support.apple.com/en-us/HT204592
It is a 2011. I haven't tried first aid 3-4 times in a row. It will sometimes get to the login screen, but soon as you try and type the password restarts. Will recycle it if I can't get it to boot. I have all of the cables to use it as a monitor and a new macbook with thunderbolt 3
Please carefully review the TDM article that I posted above.
Even if the 2011 iMac was working, the MacBook can not use it as a display.
If you want an external display for the MacBook, then you will need to buy one.
Ok, thanks. I got it to boot in the Apple Hardware test and it said no trouble. I may just scrap it and be done.
Give it a good Irish wake. I had one and it was a good workhorse.
Yeah’ it’s either a PPC or Early Intel if it started up into the Apple Hardware Test.
Older iMac Wont Start - Continually Reboots
