Target display mode blinking black

I've been running into pretty much the same issues as you, retina macbook pro, late 2011 27" iMac...I had run into the bad graphics card recall on my iMac and was hoping the replacement graphics card would have fixed the problem...nope.

I've tried all manner of turning off power mgmt, screensavers, etc and just doesn't work...I use the same retina macbook with a 27" monitor at work and it works perfectly fine...so it's definitely something specific with the iMac.

Good to know I'm not the only one running into this...it's really annoying, temped to almost sell the iMac. Please keep us all posted.

Same problem here. retina macbook pro, mid 2011 27" iMac.

The problem is not in the target display, but somewhere in the second video output circuitry, I believe. I have an older MacBook Pro (2009) and a 24" LCD Cinema Display, and I get intermittent blinking to black that eventually stops. It may be heat related. Another long-shot: Does the hard drive have a temperature-related automatic recalibration? In my older, older MacBook Pro, I was getting some extraneous buzzing in the audio section when I was converting music from vinyl records to digital format. I tracked it down to audible vibrations from the hard drive recalibration. Wondering whether today's version of temperature-related drive recalibration could be behind it.

I'm 99% sure you are having a different problem. The rest of us have a very consistent and well defined problem and yours seems complete different.

As I write this my iMac continues to blink black and I too am getting sick of this. This is also why I have this setup. It seems like the Target Mode feature isn't really highlighted or marketed and now I see why.

I haven't installed the firmware updates but I really hope they work.

Hey guys - just thought I'd chime in since it has been a while. I originally reported this issue back in April/May and just recently gave up on my open ticket with Apple Care. The amount of hours I put into capturing logs and talking on the phone with Apple Care would have covered the cost of the upcoming Mac Pro which I'm sure doesn't have this terrible defect.

I have to say that I'm disappointed with the tech support process. The issue is very easy to replicate by connecting 2 iMacs together - you can speed up the occurance of the issue by pressing the expose key a bunch of times to cause high GPU activity - as shown in the video posted earlier: http://embraceware.com/temp/imac.mov (which was also sent to Apple Care). After sending the first batch of logs and being made aware of the problem, my expected response would have been something like - "Thanks for reporting this issue - we can replicate it here in the lab. A fix will be made available in a firmware update" - or something along those lines.

My last batch of logs were rejected because I'm running OS X Mavericks on one of the iMacs - I gave up at that point.

The one positive thing is that they are clearly aware of the issue. We'll just have to wait.

I was seeing the same issue as most of you all, hooking up my MBP Retina to my imac to use the imac in target display mode. All of the sudden two days ago, the blinking stopped. I realized it hadn't been happening for a while and I noticed I had done one thing differently. I plugged the thunderbolt cable into the port closest to the headphone jack on the left side. Typically I ALWAYS plug into the one closest to the power cable but just inadvertantly plugged into the other one and no blinking.

Hi jmwickard,

That's interesting - I've tried alternating the ports as well but eventually the issue occurs. But in my case I'm connecting multiple iMacs together and not using a rMBP in the mix. Can you try openning 20+ Safari windows on each display and press the expose key rapidly to confirm there is no blinking issue? I've been using that process to test if the issue is still occurring. It usually occurs once or twice while doing that test for 60 seconds.

I just wanted to record that i'm having the same issue here...

Funny is that I reinstalled both iMac and the MacBook pro and everything seemed ok..then I updated.. then the issue returned.

It seems a regression on the OS at some point?

You all seem convinced that the culprit is the Mac OS. I'm running 10.7.5, and my target display is a 24" Cinema Display, rather than an iMac.

I wonder whether anyone here has done this:

Carefully clean the contacts in the video output port of the MPB, and the connector on the video cable.

I seem to have cured the blinking problem my Cinema Display. Perhaps not relevant to you folks, I also went back to using the MPB power cord, and not the power connection from the Cinema Display. When I went back to the power connector from the display, the blinking returned.

I have some thoughts about why I was successful, but since I'm not an electronics engineer, I'll spare you.

Harvey

Hi Harvey,

The issue occurs when a late 2012 iMac is being used as a monitor in the TDM chain. It's been confirmed to be a problem and requires a firmware update (yet to be released). All cases we're discussing here involve using a 2012 iMac as the monitor in TDM. You mentioned that you're connecting a 24" Cinema display to a Mac - not the same situation.

Same problem: Late 2012 iMac with Thunderbolt ports; recent (9/2013) 15" mbp Retina; 2-meter Thunderbolt cable. Swapping which connector for Thunderbolt not effective. Also MBP cpu or gpu sensitive. Most blanks triggered by <blank> repaints of complex documents in Pages.

New symptom: I listen to Pandora often. While it runs on iMac that is the "target display", audio consistently goes "blank" when screen blanks. Feels like a bus reset or similar of some kind.

Thanks for the long-running contributions of you other <blank> afflicted <blank> souls.