Macbook Pro 16" with UltraFine 5K display not waking from sleep

Did you try turning off Power Nap? I've been putting mine to sleep every time I leave it just to test and so far it's woken quickly every time I've pressed the space bar.

You are pointing the problem to the LG Ultrafine 5k as being problem and you may be correct. Maybe the firmware for the LG monitor needs to be updated? In doing my tests I find that when I link the 15 inch to the LG monitor, everything works perfectly, I am only experiencing these issues when I connect the 16 inch to the LG that I am experiencing the following problems:

1) LG monitor will not wake up after sleep

2) LG monitor turns on at 100% brightness

3) 16 inch will not shut down if connected to LG Monitor, it hangs in black space where you only can see the arrow and then you have to do a force shutdown.

I did download the LG Monitor app from the App Store and ran the firmware test on the LG monitor. When I get home tonight I will look to see what they say the latest firmware version is. My monitor is apparently up to date.

*may be able to rule out Catalina*

I just did a TimeMachine restore of my 2018 15" Macbook pro (already running Catalina 10.15.2) to the new 2019 16" Macbook Pro. The 15" had zero issues waking back up the monitor from sleep. The 16" has this issues immediately after restore (as it did from a fresh Catalina 10.15.2 install)

I've got the Radeon Pro 5500M 8GB version

Full specs:

64GB RAm

2.4GHz 8-Core i9

2TB SSD

5500M (8GB)

I have a new MBP 16" with LG Ultrafine 5k. This is an exact replica of my 2016 15" MBP, which ran flawlessly. Since day 1, I have had almost the same issue, I put it to sleep and my laptop screen wakes, by my LG display does not. I'm running Radeon Pro 5500M 8 GB with intel UHD Graphics 630 1536 MB.

I thought it was the 1st version of Catalina, then when the software update came out for the most recent 10.15.2 the issue pursued. I've been on the phone with Apple Support for 5 weeks trying everything. They told me it was DuetDisplay.kext and when I removed that, the issue still persists.

It's absolutely a glitch in their software and I'm frustrated at the mediocre level of support. This machine came from a time capsule backup that had no issues. It's either Catalina or the graphics card. I hope they can correct this.

We all know about the issues they had not getting the MBP screen to even turn on for some users. This has been a really sloppy software release.

I really did think it was an LG monitor compatibility issue at first, but I have similar issues, but to a lesser extent, on my HP 4K monitor as well. The LG is definitely worse, but in terms of power, the HP provides less power to the MPB than the LG does, and the LG is much worse. Sometimes both screens just flash until I unplug it and restart, and other times when I plug in, my MPB just crashes and returns to the login screen. Less often, but sometimes, it will just randomly start doing this when I am already connected and working, and I can usually unplug the LG and move the cord to the other side of the MBP to fix it. Other times I have to restart. Then after a restart it works for a day or so, then starts happening again. The problem definitely gets worse the more I have active. If I have 50 browser windows open, and 4 or 5 other apps running, the problem is worse. Everything points be back to this being a thunderbolt driver/firmware issue or something to do with the resources Catalina is dedicating (or not) to those ports. Since the 5K screens are worse than the 4Ks, I can't imagine trying to drive dual 6K's as this thing is supposed to. I had the exact same setup with my much less powerful 15" MBP and it all worked flawlessly, so it's not a hardware performance issue.

I have been experiencing the same issue with my 16" MBP and UltraFine 5K.

Processor: 2.4 GHz 8-Core Intel Core i9

Graphics: AMD Radeon Pro 5500M 8 GB

I use it in clamshell mode and when I have this problem simply reconnecting isn't enough; I have to open the laptop to turn on its display, then reconnect the UltraFine 5K.

Please someone fix this.

Just thought I would let you all know that I recently wrote to "cooperivan" on that thread on Reddit (that I mentioned above) on the same wake issue and he confirmed that the issues he had been having with his Macbook Pro 16 inch and the LG 5K not waking from sleep or the auto-brightness not working have been non-existent since he bit the bullet and replaced his older 27MD5KA-B (older model) of the LG 5K with the most recent iteration, the 27MD5KL-B. There have been no issues at all and he has had the newer model for over two weeks now. This is cold comfort, I know, for 1) those whose LG 5K monitors are out of warranty and are not willing (completely understandably, of course) to cough up the major dough to buy a new version of what is effectively the same monitor, or 2) for those experiencing issues with other monitors, like Tom DePrenda and his Apple Thunderbolt display (!), but I thought it nonetheless worth sharing. I'm currently trying to get LG to replace my more recent version of this monitor (27MD5KB-B), bought in December 2019, with the new "L" model (even if cooperivan's experience might, I can't deny, be a fluke, as I have no other evidence to go by). If LG doesn't play ball, I'm hoping (against hope?) as ever that a universal solution to these problems is in the works from Apple...

I was having this issue as well, with 10.15.3 on the 16". I have the LG 5K A model still. Was getting problems with it waking from sleep, where I'd have to unplug the thunderbolt cable and plug it back in to get the monitor to wake up, and frequent crashes while asleep. It seems to have started with the .3 release. I had to send the MBP off to get the logic board replaced, and it came back wiped clean. I installed 10.15.4 on the clean hard drive and after the first night, while the display woke fine, it had crashed over the night. Judging from the reports, it crashed within minutes of it going to sleep. Says the remoteservice process crashed.

This forum has become a mish mash of a lot of similar but sometimes obliquely related issues. So, please forgive me for borrowing the forum for my issues. That said, hopefully my input may help others.

My setup:

16" MBP running 10.15.4

2.6 GHz 6-Core Intel Core i7

16 GB 2667 MHz DDR4

AMD Radeon Pro 5300M 4 GB

Intel UHD Graphics 630 1536 MB

LG Display 27MD5KL-B

When plugging into any of the four USB C inputs, the monitor sometimes connects, sometimes not. When it does, it may stay connected for a period of time, after which it disconnects. It they repeatedly tries to reconnect multiple times, each time playing a chime (power connection chime). This is true whether it's open or in clamshell.

I have tried SMC and PRAM and NVRAM resets. I unplugged the display for a bit and plugged back in. I have a second display that is several years old. The 16MBP worked fine on it, but I may not have tested it long enough. I have read that interference can cause issues, but I am not near a router. That said, I moved the display to a different room and it seemed to work. Again, this may be because I did not test it long enough.

I decided to plug the power brick into the MBP at the same time I was plugged into the display. So far, this is the only thing I have been able to do to get the display to work consistently. I have read that the 16" may want more power than the display is giving it. Not sure if this explains why the display works when using the power brick. But, I thought I would at least try to contribute to the discussion.

I'm of course here with exactly the same problem. There was some suggestion in the thread that it's an MBPr issue, or the UltraFine 5k being the issue, but I think it's a combination of the two that is the problem, perhaps video card specific but who knows. I just know that Catalina has been a complete garbage release from a quality perspective; just one thing after another. Here's my setup:

• 2019 iMac (non-Pro) 27 with retina 5k and Radeon Pro 580X 8GB card with this exact same UltraFine 5k monitor (27MD5KLB) - zero issues at all with the monitor waking from screen power off (I never sleep that computer). I tested letting it sleep though, not deliberately putting it to sleep, and the monitor woke up fine.
• My MBPr 16 has the Radeon Pro 5500M 4 GB setup, and at a different location I have two LG UltraFine 4k's (model 24MD4KL). Those displays never have this issue.
• I just received an additional UltraFine 5k yesterday to use with my laptop at a different location, and have been running into this problem more often than not when the screens are supposed to wake. The laptop is remaining on and open, I just have the displays turn off after five minutes.

So, same monitor, non-laptop Apple computer, same OS; no issues. MBPr 16, same brand of monitor; no issues. MBPr 16 and the 5k, issues.

Pretty frustrating, as is the case with most Catalina BS that never seemed to occur in previous releases.

FYI - my local apple store thinks this is a hardware issue and has agreed to return my 16" and give me another one.

Thanks for placing your solution. I forgot to mention it. Yes, sometimes it does work to just select sleep and then waking up the Mac. For me it is sporadic (out of 5 tests it worked twice) but I would highly recommend trying it, as it is a lot easier than pulling out cables.

I am currently working with an HP 27" 4K Z series monitor and the same problems exist, but are much less persistent. If I plug/unplug a couple times, I can get the 4K to work, but not the 5K... It honestly seems like the GPU just can't handle the 5K output consistently. The fact that it has gotten worse over time is what's most unusual, unless it is failing hardware.

Tom, if you are having problems with both your MBP monitor and the LG monitor, I would recommend you have the hardware tested. One person in this discussion has had their MBP 16 replaced after taking it into the Apple Store.

I had this problem on a 16" MPB I purchased in December. I tried everything (noted in prior posts) and my Apple rep agreed it was a hardware problem and ordered me a replacement and let me return the first one. This is 2.4 i9, 64GB, 8GB Pro 5500, 4TB. I had the exact same problems with the new replacement out of the box...