Thunderbolt Display turns off randomly

No news here, just another data point for anyone who still cares. 😁

tl;dr: another instance of this issue improving with an external Thunderbolt cable.

2011 Mac Mini Server with Thunderbolt Display that started blacking out after 5+ years of being awesome. The blackouts increased in duration from 1-2 second flashes that recovered autonomously to apparently indefinite darkness that required a monitor power cycle or signal cable unplug/replug to recover.

I tried:

• PRAM/SMC reset, multiple times.
• Display settings hoakus poakus:
  • reduce brightness
  • disable automatic brightness adjustment
  • disable power save
• Software updates

  All updates to TBD and Mac mini had been applied already. Even so, I downloaded and launched the standalone update installers from support.apple.com. Each installer indicated that the update was already installed.

The frequency of the blackouts had been increasing over the course of the last few weeks, until reaching a crescendo over the weekend where the display would remain illuminated for only a few seconds before needing another power cycle or signal cable dis/re-connect.

The number of posters to this thread who found relief from this issue by using an external Thunderbolt cable gave me hope. I picked up a new Thunderbolt cable from my local Apple Store today, and for the first time in a few weeks my TBD has been solid for more than a couple of hours.

I've seen enough posts in this thread to know that victory can never be declared on this issue, but I'll post updates over the next few weeks as I suspect at least a few folks are in my situation and ready to buy new hardware when Apple freshens up the desktop offerings. Until then a working TBD is the best possible setup for me.

A lot of Thunderbolt Displays with 'black screen' issues suffer from cables with 'burned' chips in the connector ends. Using a fresh external cable is of course a lot simpler then replacing the internal one.

If your issue persists with a fresh cable, then the cable is probably not the cause of your display flickering / shutdown issues.

Same problem here - I see this only happen with the external socket from the back. If instead I use the monitor's own pre-attached cable, there is no issue for months. I took the display to my local Apple center in fear of the problem exacerbating. They diagnosed a "possible faulty Logic Board", replaced it and charged me $250. Less than 8 hours later, the problem was back!

This is just a heads up for anyone with the same issue. It clearly is NOT a Logic Board problem :/ At least not in my case.

The plug on each end of a Thunderbolt cable contains tiny micro chips. They tend to get pretty hot. After some years of usage they begin to produce errors. Simply replacing the cable is the cheapest solution to fix the black outs. This is true for both the pre-attached cable and for external cables.

I have had zero blackouts with a brand new external cable for almost a full week now. I'm sure that there are different situations that cause the blackouts for others, but the cable seems to be the trick in my case, and fortunately it was inexpensive to try.

My next step will be to have the internal cable replaced, but for now it's really nice having my good old thunderbolt display working like new again.

Concur.

Though in my ( late-2014 MacMini, OSX El.Cap 10.11.6 ) case, unplugging & re-plugging my 'Foreign' monitor ( which is connected via an APPL DVI-to MiniDisplay port adapter) from/to the Thunderbolt port failed to cause OSX to re-enable the video signal. Disconnecting the 'foreign' display's DVI plug from the DVI adapter and re-connecting that, though, did cause OSX to re-enable the video signal.

Apparently all this has nothing to do with hibernation, sleep/wake, or screensavers, as I could 'ssh' into the Mini and see everything running, with no screensaver process, and further characters from my attempts to get the display to light up before unplugging and re-connecting the DVI were scribbled right into an open text editor which was still up along with everything else on my desktop when the display lit back up.

... Implying the ( SystemPreferences-> 'Turn Display off after' ... not set to 'never' ) feature is a security vulnerability, as the kb+ms are still 'live', OSX is still up and running, and no authentication challenge is presented. .. at least for ppl able to compromise systems without seeing what they're doing.

Try this.

Unplug the power for 10 second to your display then turn it back on.

Then go to System Preferences, Energy Saver, choose the “Turn Display off after:” to “Never”.

It is not the power problem or the cable problem of the firmware issue!!!

Good Luck

Aaah ... earlier I had seen run some people comment about replacing the monitors built-in wires, and had missread the latest posts thinking that was the solution you guys had used.

I have the .5 meter Apple external cable and my issue persists ... the "never sleep" option seemed to help last night, still had a flicker or two, but no shutdown.

Thx

Well, you guys were right -- but with the external and replacement internal cables both being relatively inexpensive, I have used/replaced both and the issue persists. The monitor settings trick seemed to help for a while, but we're back to square one.

The situation is that it basically has to be unplugged once it goes dark -- so anyone have any experience with that? Maybe whatever power management it uses (anyone know if that is its own piece, or is it on a larger "motherboard?")

I had this problem and it turned out to be a thermal problem with the graphics unit in the Mac Mini overheating. Since I installed Macs Fan Control and tied it to keeping the GPU temperature within range, I have not seen the problem recur a single time, for many months. Recommend checking this simple software fix before replacing any cables.

Same problem here.

5k iMac ( Late 2014 ) with two 27" TB Displays. One of the displays started all the symptoms months back. Jumped through all the hoops ( SMC, settings, new cables, etc... ) , with limited positive results each time. Yesterday the display went dark. Hooked it up to 2 separate iMacs and the display stayed black.

Wondering if this should be a recall by this point?

Apple Thunderbolt Cable (2.0 m) - White - Apple

I have the same issue as you after done with Thunderbold Display Firmware Update 1.0. Mac mini 2011 with all latest system, driver and firmware. I think it's the display firmware update 1.0 caused this issue. Do not have this issue before firmware update.

I have the same setup as you with the latest updates and am experiencing the same problem. I received the unit today and had the issues appear after the firmware update.