I purchased a 21.5" 2017 iMac and I want to use it as an extended display for my MacBook Pro (13-inch, 2020, Four Thunderbolt 3 ports). I bought the Thunderbolt 3 (USB-C) Cable and have tried Command F2 but nothing is happening. What should I do?
iMac 21.5″, macOS 10.15
And 2020 Macs can no longer take advantage of Target Display Mode:
From the now-archived support TDM article:
Target Display Mode does not work with iMacs newer than Late 2014.
"iMac (Retina 5K, 27-inch, Late 2014) and later iMac models can’t be used as Target Display Mode displays."
dialabrain is 100% correct. If your MBP needs an external display, please buy one for it. Using your 2017 21.5" iMac is not the solution.
Using 2017 iMac as extended display for 2020 MacBook Pro
