10.12.4 display sleep bug

Have the same issue with iMac 5k + 2 other displays setup. The main iMac 5k quite often does not wake up from the sleep mode, but other 2 displays do. The left one acts as a primary and nothing helps (manual sleep and then wake up again, switching off the screen etc.), just reboot. Really annoying.

So far for me shutting off the two external monitors before the iMac goes to sleep is still working for me and while it is a work around it at least works.

I have re-installed the OS, reset everything several times with little success. But as long as shutting of the external monitors work for now I am ok with it till the Apple Engineers can figure it out. I don't like it but cannot fix it by complaining or otherwise.

I have this same issue.

Details: Macbook Air, early 2014, external Acer S241HL monitor via Thunderbolt. Reset SMC and NVRAM to no effect.

I actually had this issue, though far less frequently, before I upgrated to 10.12.4. Now, however, it happens every time the Air sleeps.

I too have been in touch with Apple regarding this. I've supplied them with the sysdiagnose and a file called "iMac.spx". The AppleCare rep (Todd Seydel) has really been very responsive so I'm hoping this can be resolved soon. For the moment I've just turned off power save on my displays and set it to a black screen saver. Not really any sort of power saving but at least I don't have all three monitors lit up 24/7. As Bryston said, I too will post if I hear anything. But hopefully we'll see an OS update soon.

I have the same problem with an original Apple Cinema Display (DVI connected).

It become appears after some time. Not only the sleep does not work, but "blank screen" hot corner does not work anymore too—login screen appears instantly. Really annoying, turning off MacBook Pro every time I need to go away from computer is not fun.

same issue with a late 2016 MacBook Pro 15" and a Dell 42" 4K monitor. Extremely annoying as one has to force shutdown the machine and reboot it. I'm not amused apple to get a new bug built in in a 10.x.4 Release!
When is this going to be fixed?

Sadly, this is proving to be my experience as well.

I returned to my iMac Retina after a long weekend, and the main display was off. 😟

The satellite Dell displays were still working, though, and I was able to logged in. When I looked at the Displays pref pane in System Preferences, it was showing both satellite displays, but the main display was gone!

I'm not sure what I'm going to do next.

Hi All,

Energy Saver "Turn display off after..." is what is causing the issue. Set that to "Never" and pick a dark screen saver to activate after a few minutes. I have a login screen activate after interrupting the screen saver. That works fine. I do not think much power is being wasted since LEDs are pretty efficient. Hopefully Apple gets a fix in soon and lets us know so we can change setting back to normal.

Sadly, this doesn't work for me.

iMac 27 5K - Tried NVRAM/SVC reset, disconnected 2nd monitor & all USB devices, killed all power saving options.

Any time from 2 to 20 minutes after logging in, black screen and need to hard reset.

no problems before 10.12.4

I can confirm that the SMC Reset doesn't last - which is pretty bizarre when you think of it. Lasted a couple of days.

I will also state that I was not handled very well by Apple support - my system is still under warranty and I have AppleCare.

They have not asked for any diagnostic info.

They just told me to reset SMC and reinstall the OS. Pointless.

No further communication.

And let's see if they have a fix out before WWDC - I doubt it.

If they don't, it turns out I won the lottery and actually got into WWDC this year, and so I have something to chat with Apple about.

Changing Energy Saver back to Never turning off displays.

I also use a Dell monitor with my 27 inch late 2012 IMAC and have had the 10.12.4 display sleep bug since the recent OS update to Sierra 10.12.4. After unsuccessfully trying several

possible fixes, I updated the Nvidia web driver. Specifically, I downloaded and installed Nvidia web driver 378.05.05.05f01 package and installed it. The problem has not reoccured since I did this.

Same here. A Dell 4K at the left and a dell "2,5k" at the right.

At this point, only the iMac (in the middle) has gone black. So I was able to restart using the Dell/external screens.

But today all screens went black. Had to use the iMac button restart. Arghhh!

Apple has "introduced" monitor issues since 10.7 (maybe earlier). Before that there was no problem. They were the leaders in this area. After that there has been all kind of issues with multi screen setup.

Suffering from the same issue. Mid 2015 iMac 27 + Dell 4k + Cinema Display.

I have been on developer beta builds and this issue started immediately after introduction of "Night Shift" feature in one of the incremental updates. I guess some low-level support code added for this new feature started causing this issue.

I have a 27" iMac11,3 May 2010, 20GB ram with a display/wakeup problem.

It did not occur until after the Sierra 10.12.4 update.

I do not have an external monitor.

After wakeup, sometimes the system shuts down, sometimes the system reboots.

I also have this issue. iMac (Retina 5K, 27-inch, Late 2015, VESA option), Radeon R9 M395X, 32 GB ram, with 2 Dell p2175q monitors connected via mini display port. Also on macOS Sierra 10.12.4.

Typically after a longer sleep (10+ minutes), the iMac display will not power up, but the external monitors will. I've seen a few cases of just prior to completely wake up, the iMac display will flash some life for a moment, and then power off, leaving just the external monitors alive. A majority of the cases of this issue result in the iMac display not coming on at all, with the external displays powering up and displaying a portion of the desktop without issue! The only solution to get the iMac display going again is to reboot.

I've tried changing various Energy Saving options, including disabling Power Nap. I've reset SMC and PRAM, with no change in behavior. Night Shift schedule is "Off" and have never enabled the feature.

If it helps any, my usual method of getting the displays to go to sleep is using the "Keychain Access" Lock Screen feature from the menu bar in the status icon area.

I have never experienced this issue until the 10.12.4 upgrade, so I suspect it's something to do with this new version.

Edit: Absolutely happy to assist in debug/logging for Apple if they give me a buzz.