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My iMac doesn't extend display from MacBook Pro

Hello.

I am having trouble with extending display of my Retina MacBook Pro 13" from 2015 onto my 2011 21.5" iMac. I tried pressing CMD+F2 on my iMac, and I tried a lot of troubleshooting steps (such as unplugging the power cord, waiting 15 seconds and plugging it back in and waiting 5 seconds before turning it on), but nothing helped. I have an Apple Original Thunderbolt 2 cable and I have it connected properly and it doesn't work, however the cable is detected.

Can you please help?

Posted on Apr 30, 2020 10:07 AM

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Level 10

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Posted on Apr 30, 2020 10:29 AM

All iMac models introduced in 2011, 2012, 2013, and mid 2014: Use a Thunderbolt cable to connect your iMac to a Thunderbolt or Thunderbolt 2 port on the other Mac. If the other Mac uses Thunderbolt 3, you can use the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter with your cable.

Target display mode requires macOS High Sierra or earlier on the iMac used as the external display. It does not work with macOS Mojave or later.

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Apr 30, 2020 10:29 AM in response to tin225

All iMac models introduced in 2011, 2012, 2013, and mid 2014: Use a Thunderbolt cable to connect your iMac to a Thunderbolt or Thunderbolt 2 port on the other Mac. If the other Mac uses Thunderbolt 3, you can use the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter with your cable.

Target display mode requires macOS High Sierra or earlier on the iMac used as the external display. It does not work with macOS Mojave or later.

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Jun 1, 2020 3:53 AM in response to tin225

Using a different keyboard actually fixed the issue.

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May 1, 2020 10:57 AM in response to tin225

Might see this...

https://discussions.apple.com/thread/251312337?answerId=252559703022#252559703022

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Apr 30, 2020 10:58 AM in response to BDAqua

I use High Sierra and both computers use Thunderbolt 2.

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Apr 30, 2020 3:29 PM in response to tin225

I haven't actually seen anybody using a 21.5" iMac for a Display yet, but from Apple's notes it seems it should work. :(

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Apr 30, 2020 11:34 PM in response to BDAqua

That's weird! I modified nothing.

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May 1, 2020 12:50 AM in response to tin225

I also read the full guideline and warranty documentation that came with the Thunderbolt cable, which was actually shorter than expected.

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May 2, 2020 4:50 AM in response to BDAqua

I don't have a black screen...

It plays my alert sound effect when I try and press CMD + F2 (including FN)

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Jun 1, 2020 8:03 AM in response to tin225

Great to hear, thanks... what KB didn't work?

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Jun 2, 2020 4:45 AM in response to BDAqua

The A1048 that came with my iMac.

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Jun 2, 2020 7:34 AM in response to tin225

Thanks. :)

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My iMac doesn't extend display from MacBook Pro

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