My 16 inch MBP all the sudden stopped waking up the LG 4K display it's connected to. Oddly, it's still getting a charge from the LG monitor, and when I reboot the computer it will suddenly wake up the LG screen and work, but once the MBP goes to sleep again, and then wakes up, the LG monitor won't wake up without a reboot of the MBP. Has anyone else had this issue?
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16 MBP Stopped Waking Up LG 4K Monitor?
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Yes! I've been having this problem for weeks with my 16 inch MBP and the LG 5K Ultrafine. It wakes up randomly but usually does not. Once in a while it doesn't even from a cold boot. The only reliable way to get it to wake it to yank the cord. USB devices plugged into the back seem unaffected.
It worked fine for the first month or so I had the new laptop (and never had it with the 2016 MBP). Seems to be some sort of driver issue.
How old is your 4K? I've been reading in this thread some people think it only affects early versions of the Ultrafines:
It worked fine for the first month or so I had the new laptop (and never had it with the 2016 MBP). Seems to be some sort of driver issue.
How old is your 4K? I've been reading in this thread some people think it only affects early versions of the Ultrafines:
My LG 4K is pretty old, I got it a couple years back when they first released these. It's definitely an early version. Oddly though, mine doesn't even wake up when I pull the USBC cord out and in, it will only bring the screen up with a reboot. Very strange all around here.
I updated the LG 4K software via LG Screen Manager and this situation seems to have improved, at least for now.
Hey man, may I ask you a question?
I have a 4K 24" Dell and am thinking about switching to a 22" Ultrafine becsause 24" is too much for my eyes to travel.
What iteration of the 22" Ultrafine would you suggest?
Thank you!
I have had both, first 21.5 ultra fine and then 24 ultra fine. The 21.5 was handed down to someone else in the office.
Keep in mind the 21.5 is USB-C only and supplies only 60w of power and the usb-c ports on the rear of the monitor will only work at usb 2.0 speeds.
The 24 is thunderbolt 3 with 85w of power and the ports on the back are full speed and also have one additional TB port.
The DPI is “lower” on the 24 but not too noticeable to me at normal desk distance.
The 24 works perfectly with my 2019 15 inch. None of the wacky problems you see with the 16 inch.
Same issue on the MBP16 with the screen not waking up. If I open the laptop, the screen just flashes on and off and only disconnecting it from the display returns it back to normal. Then I have to restart the computer for the monitor to work again.
What could be the problem?
What could be the problem?
I am cautiously optimistic. The random issue where waking from sleep would fail has not repeated since yesterday's update. It seems like every morning I have to restart the machine, but not today. I'll report back after a few more days.
Ok, so today is Friday and the issue seems to have been fully addressed. But... now the screen will blink once in a while for no apparent reasons. It's literally a split second refresh. No idea if this is a new bug or something completely unrelated.
Either way -- I have yet to have a wake-from-sleep issue!
Either way -- I have yet to have a wake-from-sleep issue!
I have 3 UltraFine 4K connected to my new MacBook Pro 16-inch. Those three UF 4K I got was purchased from Amazon as renewed, so they are pretty old model I believed.
It was working fine on my old mbp (the 2017 15-inch model), after I switched the new 16-inch model, it stopped wake up from sleep from time to time, and usually two out three wake up fine and the one does not wake up usually can be fixed by replug-in the usb-c cable. however if it does not work by replug, it will be a very serious problem, makes you crazy because the whole OS will crash 100% time, the screen turn to mosaic and it halt, nothing is responding. after 1 minute or two, it will automatically restart or you have manually press the power button to force it restart, you will lost all unsaved work, it's very annoying...
I can understand if there is a bug on GPU driver or whatsoever cause it problem at wake up but hopefully it should not crash my macOS in anyway so I can keep trying or manually restart the OS after save my work.
It was working fine on my old mbp (the 2017 15-inch model), after I switched the new 16-inch model, it stopped wake up from sleep from time to time, and usually two out three wake up fine and the one does not wake up usually can be fixed by replug-in the usb-c cable. however if it does not work by replug, it will be a very serious problem, makes you crazy because the whole OS will crash 100% time, the screen turn to mosaic and it halt, nothing is responding. after 1 minute or two, it will automatically restart or you have manually press the power button to force it restart, you will lost all unsaved work, it's very annoying...
I can understand if there is a bug on GPU driver or whatsoever cause it problem at wake up but hopefully it should not crash my macOS in anyway so I can keep trying or manually restart the OS after save my work.
The issue in my case was the Thunderbolt cable that comes with the LG.
Yesterday, I purchased the 27" 5K Ultrafine monitor for my M1 MacMini directly from Apple and was very apprehensive before I plugged it in. Especially after reading about all the issues with it. Everything worked fine. However, this morning, the monitor would not display anything. I tried unplugging the power cable and the Thunderbolt cable and still nothing.
I then plugged it into my MacBook Pro and still nothing. In the heat of anger, I was getting ready to box it up and send it back, but thought, 'Hey, let me try a different cable'. I had an Apple Thunderbolt 3 Pro cable that I used with my old BenQ monitor. And, voila! It worked again. I had planned on selling the Pro cable to offset the cost of the LG, but now I have to keep it!
I plan to order a second LG next week and I'll see if I have the same issue. I'll even try the Thunderbolt cable from the new one on this one. So, I really feel that some of the issues with these LG Ultrafine monitors is a faulty cable. If I didn't have a Pro cable to use, I would have sent it back.
Yesterday, I purchased the 27" 5K Ultrafine monitor for my M1 MacMini directly from Apple and was very apprehensive before I plugged it in. Especially after reading about all the issues with it. Everything worked fine. However, this morning, the monitor would not display anything. I tried unplugging the power cable and the Thunderbolt cable and still nothing.
I then plugged it into my MacBook Pro and still nothing. In the heat of anger, I was getting ready to box it up and send it back, but thought, 'Hey, let me try a different cable'. I had an Apple Thunderbolt 3 Pro cable that I used with my old BenQ monitor. And, voila! It worked again. I had planned on selling the Pro cable to offset the cost of the LG, but now I have to keep it!
I plan to order a second LG next week and I'll see if I have the same issue. I'll even try the Thunderbolt cable from the new one on this one. So, I really feel that some of the issues with these LG Ultrafine monitors is a faulty cable. If I didn't have a Pro cable to use, I would have sent it back.
The problem: The 5K LG Monitor Ultrafine that Apple sold intermittently while they were creating their own doesn't "auto wake up" or stays dead. The MBP sees it enough to produce sound through it, and use the camera, but the monitor never wakes up.
The research: I see hundreds of threads out there with this issue (including ) but after hours of reading each one, there never was a fix. Some had success with a reboot or an unplugging of the monitor, but most did not.
The fix: You literally have to use the EXACT same cable that LG sent with the monitor (and) plug it in on the left / rear USB-C port . Watch an old unboxing video (
Why: A real thunderbolt USB-C cable doesn't appear to be enough ; I'm guessing that the frequency must be perfectly achievable or the monitor doesn't think it's connected. This is likely needing a 5A 100W cable Gen2, but I didn't even have success with this one : ( https://www.amazon.com/USB-C-Cable-...&qid=1615671733&sprefix=5k+LG+,aps,187&sr=8-6 ).
I'm going to search to find out more, but this question was asked so many times in the Apple community and I thought perhaps others may benefit from my hours of swearing ( er, troubleshooting ).
jasonCbraatz
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