10.9.3 external display not recognized after sleep

I am having this issue with my Late 2011 MacBook Pro 13 inch. I can't get the external monitor to work after updating to 10.9.3. I also have this issue on my Mid 2013 MacBook Air. I can't get the external monitor to work on that machine either.

I've even bought a new thunderbolt to HDMI adapter thinking it may be bad. The new one doesn't work either. Then tried a different monitor, still can't get it to work.

I've come across this for my HDMI connected monitor when re-awakening from sleep mode. I'm running 2 monitors one with HDMI and the other is using the mini-displayport->DVI-D.

As a workaround I generally turn off the HDMI monitor when in sleep and when awakening (use the other monitor to let me know when it's awake), I just turn the screen back on and it detects.

Annoying I know, you'd wish these update wouldn't just introduce weird bugs and break things.

I have the same issue.

Yes I see something similar on my two month old rMBP 15 (discrete graphics). In 10.9.2 there was video on the monitor (dim desktop) when waking from sleep and the login screen is dispayed. In 10.9.3 there is no video and if I don't log in before the monitor goes into its sleep mode, the rMPB does not recognize the monitor. No amount of cable jostling or power off/on will kick things off, I have to restart the rMBP for the system to be back to normal.

I could shoot myself in the foot for upgrading as 10.9.2 was so seemless.

Has anyone filled out a bug report for this?

Please file the bug.

I've got the same issue, new Macbook Air with all updated... 😠

I call to Apple Support and we execute a process to reestablish the controllers and erase the cache memory.

Here is what to do:

Shut down the computer and connect the power supply.

Now, everybody should press:

Shift + ALT + CMD and then the Power Button. Check the color of the light on the Power Cord, it should change from amber to green and come back to amber.

Then, press:

ALT + CMD + R + P + the Power button. With this you are erasing the video cache memory.

Restart your computer and it should be any problem now.

It works for me, good luke fellows!

I had a very similar issue. I updated yesterday to the new 10.9.3 with the support for 4K monitors (which I do NOT have) and it broke my Thunderbolt display.

Here's what happened, I updated and after the reboot, my Thunderbolt was "active" meaning the screen was on and peripherals worked that were attached, but I only had a black screen. The mouse would show up on the screen as well. I checked brightness and resolution, but nothing showed up. When I changed the rotation, the screen would flash on (showing my desktop background) and then flash off.

So the solution above by cristobal.sandoval worked, but the directions he gave are not exactly how it worked for me. First, I have a Mid 2012 15" MacBook Pro with Retina Display. So I powered off and the did what the post above says, I held down Shift-Alt-Cmd and pressed the power button. No status change on the power cord's LED occurred. It booted up and my Thunderbolt was gray now, instead of black as it was.

I attempted it again but no change.

Then I just went straight for part two. From a completely powered off state, I pressed Alt-Cmd-R-P-Power and held it down until I heard the Mac Chime two times. It chimed once and then went black for a few seconds and then chimed again. I released the buttons and both my monitors are working again as before the update. Just wanted to post a little extra detail in case other people are experiencing the same issue. What a weird bug in an update. I feel sorry for the people who don't know how to fix problems themselves and will be stuck with this bug until Apple releases a new update.

Thanks for posting. This seems to be the SMC and PRAM reset steps, I think others have tried with and without success. On the second reset try my system works better, but there still is an annoying delay waking up the external monitor. If the latop was displaying a window there before the sleep, it will eventualy return there after wake, but displays on the main screen first... which resizes the window.

Same issue fro me.

I've tried to reset both SMC and PRAM but no result.

This is very annoying.

I was able to get mine to work for a bit after I reset the PRAM and reset the monitor to factory defaults (which it was on to begin with). It worked up until yesterady and then just stopped. I tried doing the PRAM Reset and montior factory default again and it didn't work.

Clearly is an issue with the latest patch, as a workaround for me as I use 2 monitors and that happens to my HDMI connected monitor, I just turn it off during sleep and turn it back on when the machine is awake and it detects every time.

I am having the exact problem with my nmp. Using external 4k (UHD) TV connected via HDMI. Waking the HDMI connection from sleep doesn't work. The computer is on and running, but display shows no input. Started happening with 10.9.3, I believe.

Yep, same as me. Just turn it off when you sleep the machine or just before you awaken it. Annoying, I know as this didn't happen prior to the 10.9.3. update.

Just a note that if either Aperture or FCP has a window open on the external display when the machine sleeps, those apps need to be quit before the external monitor is detected. Otherwise my rMBP seems to have settled down 90% of the time... but if I don't wait untill the OS displays the dimmed desktop on the external monitor before I type in the password, all bets are off.