TDM not working

Hi guys,


could anybody help me how to get TDM working?My iMac is a 27" iMac (Version 13,2) and my Macbook is a Macbook Pro (Version 10,2) (13" Retina) and i use a Thunderbold Cable.

I tried as explained by Apple CMD+F2 and CMD+FN+F2 but nothing happens.


Thank you!

iMac, OS X Mountain Lion (10.8.5), iMac 13,2 680MX

Posted on Jan 26, 2014 4:49 AM

Reply
16 replies

Jan 26, 2014 5:44 AM in response to SeaPapp

I'm using the Apple Bluetooth Keyboard. I checked all connections, both sides (iMac and Macbook) are plugged in and I'm using an original Apple Thunderbold 2m cable.


Yes it sounds like I'm doning everything correct. Only the OS X Versions are different: my iMac runs 10.8 Server and my Macbook 10.9.


Is this perhaps a global issue?

Jan 26, 2014 8:33 AM in response to L'Man

I found this in another thread


On the back of my iMac it is hard to see which way the Thunderbolt cable is actually suppose to be installed .. and IT IS POSSIBLE to connect it in the wrong orientation.


The FIX: verify your cable is connected to the iMac and Laptop in the correct orientation.


Also if you're sure the cable is correct you might try resetting the PRAM

Shut down your Mac.

Locate the following keys on the keyboard: Command (⌘), Option, P, and R. You will need to hold these keys down simultaneously in step 4.

Turn on the computer.

Press and hold the Command-Option-P-R keys before the gray screen appears.

Hold the keys down until the computer restarts and you hear the startup sound for the second time.

Release the keys.

Jun 9, 2015 9:55 AM in response to SeaPapp

I bought a high spec Macbook pro 15' retina display and a few months later I bought a iMac 27' retina display for my wife as a retirement present. My kids wanted to use the retina display for gaming and I wanted to work at home with the big screen. I called Applecare three times and after two hours in total of talking a senior technician told me it's not supported and it's that it's my fault for not checking the spec. The only reference I can find on the apple support group pages was in TDM frequently asked questions. My view is it's rediculous that Apple do not state in the technical specs for the iMac retina 27 inch the problem with TDM. TDM is a basic computer function which I have been using for years. Increase the computer spec, decrease the functionality, charge the maximum and pay little UK taxes seem to me to the way forward. The "nothing to do with me" attitude of Apple staff when a problem occurs drives me nuts.

Jul 7, 2016 10:59 AM in response to SeaPapp

*my iMac is from 2011 though (forgot to mention that), my macbook from 2015. It was nowhere stated that this wouldn't work (or not that i could find) and there's not a single article on internet that can solve this problem..

It could be related with the fact that i opted for the custom 2,8 ghz processor and not much people have this problem for that reason, but i highly doubt that. I contacted apple several times about this problem and they failed to offer a solution. So basically it's not their problem but mine...

Jul 7, 2016 4:41 PM in response to vuldermort

vuldermort wrote:


they said it was a problem with my macbook's keyboard. They replaced my keyboard, touchpad and topcase yet it still didn't work afterwards...

Wait........WHAT??? I don't use TDM but the source computers keyboard has nothing to do with it. You press Command F2 on the keyboard connected to the target computer.

Use Target Display Mode

Follow these steps to start using your iMac as a display:

  1. Make sure both computers are turned on.
  2. Connect the Mini DisplayPort or Thunderbolt cable between the two computers.
  3. Press Command-F2 on the keyboard of the iMac that you want to use as a display.

After you press Command-F2, your iMac displays the desktop from the connected Mac.

Jul 8, 2016 6:45 AM in response to SeaPapp

Yeah, i meant macbook pro indeed. I know the macbooks keyboard should have nothing to do with it and i did follow the correct steps, i tried everything they suggested: logging out on the iMac, resetting both my macbook pro's as my iMac's PRAM etc...

The thing is that it does work with the same iMac and my dad's 2011 macbook pro, my brothers 2013 macbook pro and my friends retina macbook pro (earlier model though). yet it doesn't work with mine so the problem lays in my macbook pro.Thunderbolt bridge doesn't seem to work either...

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TDM not working

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