SOLVED Target Display Mode Half Working

[Jeff001]

I've connected my late-2009 27-inch iMac as a second monitor via Target Display Mode to my newer - iMac Retina 5K, 27-inch 2017 - iMac. Both iMacs have the latest OS available. When I "command-F2" the older second monitor, I see a "grayed-out" top tab bar from the newer iMac, but nothing else from the newer monitor. Applications on the newer iMac don't appear on the older monitor, but the grayed-out tab bar displays the text name of the app that is open. Adjusting the volume on the newer iMac causes a corresponding "sound icon" change on the older monitor. So I'm getting a connection, but just not a complete connection.

Anyone seen this before, or know what I'm doing wrong?

 

[Cory Cooper]

Hello and welcome.

I haven't used Target Display Mode before personally, so maybe some of the troubleshooting here will help: Use your iMac as a display with Target Display Mode

Hope that helps,

C

 

[Jeff001]

Thanks for the response, Cory. I did check that page and many more like it. Still have connection, but not fully so.

 

[Jeff001]

Problem solved. For some reason I needed to restart the older monitor. Once I restarted, Target Display Mode worked as intended. I'm assuming, however, that Target Display Mode does not support splitting an application window over two monitors. An application window cannot be half on new monitor and half on old monitor (at least on my set up). I can, however, drag tool pallets - and entire open application windows - to the old monitor while working in PhotoShop, Word, etc. This is primarily what I wanted the second monitor for.

 

[Cory Cooper]

Glad you resolved it. Sometimes that is the best first step - "Have you tired turning it off and on again?"

Correct, windows cannot be partially on both...has to be one or the other. Thanks for letting is us know the solution.

C