Macbook Pro 2020 wont connect to Imac late 2012 by thunderbolt

[Nw2]

Hi

Ive just received my new Macbook Pro 2020 and from time to time I want to use my still perfectly working Imac late 2012 as external monitor. The Imac has a thundebolt connection and the Macbook Pro 2020 had Thunderbolt 3 (USB-C) connection. Both are running the newest Catalina. So I purchased the official Thunderbolt 3 to Thunderbolt 2 adapter with a Thunderbolt cable. According to the descriptions on the Apple website I should be fine by connecting the Imac and Macbook with these cables and ten press CMD+F2 or CMD+FN+F2. But nothing happens. Not when logged in, not in the login menu.

I noticed that in the keyboard preferences there is no shortcut mentioned for CMD+F2. I also cant seem to add a shortcut. Dont know if this causes the problem?

I have no clue what goes wrong...anybody that can help me out?

 

[Nw2]

In system overview on the iMac and the Macbook Pro it says under Thunderbolt that no device is connected at all. Switching ports doesnt make a difference. This suggest that there is a more fundamental problem right? Faulty cable or adapter? Although they are brand new?

 

[satcomer]

In system overview on the iMac and the Macbook Pro it says under Thunderbolt that no device is connected at all. Switching ports doesnt make a difference. This suggest that there is a more fundamental problem right? Faulty cable or adapter? Although they are brand new?

It has to due to Apple Security! You must invite Security pane in the RecoverMode!

 

[Nw2]

Somehow both MBP and iMac recognize each other now without doing anything in recovermode. So the cable is working. But still CMD+F2 or CMD+F2+FN doesnt work, not even with a virtual keyboard.

 

[Nw2]

Found it... I didnt read the part on the Apple site that since Mojave Target Display Mode is nog longer supported... And Iam running on Catalina

 

[satcomer]

Found it... I didnt read the part on the Apple site that since Mojave Target Display Mode is nog longer supported... And Iam running on Catalina

if you read my post I told you you have to turn off security to allow that function in the Repair menu item for security pane to defeat The T2 security stopping you!