Problems with 2016 13" MBP and USB-C monitor (LG 27UD88)

[jun180]

Hi all,

I have an issue with the LG 27UD88 monitor that pops up intermittently and was hoping to get some help.

Some context:

• This monitor is USB-C enabled, so it’s just a single USB-C cable plugged into the USB-C to my 13” 2016 NTB Macbook Pro to provide video signal to the display and charging for my laptop.
• I have my laptop constantly plugged into the monitor running in clamshell mode.
• I have a Bluetooth keyboard and mouse, and usually clicking either one of these will wake my laptop and also fire up the monitor, which will then display the login screen.

The issue:

• The issue occurs when waking the laptop from sleep. I use the Bluetooth keyboard or mouse to wake the laptop, but there is no response from the monitor and it is still in standby mode.
• If I open the laptops internal display, I can see the screen has turned on but is showing a black background and the mouse icon only, but no response from OSX to any other inputs.
• If I try and disconnect USB-C cable, the internal screen on the laptop seems to adjust its resolution, but still displays a black screen and no response from OSX.
• This issue occurs in Sierra, and High Sierra.

Does anyone have similar issues, or able to provide any guidance to fix this issue?

Thanks,
Jun180

 

[peterb123]

...

• If I open the laptops internal display, I can see the screen has turned on but is showing a black background and the mouse icon only, but no response from OSX to any other inputs.
• If I try and disconnect USB-C cable, the internal screen on the laptop seems to adjust its resolution, but still displays a black screen and no response from OSX.
• This issue occurs in Sierra, and High Sierra.

Does anyone have similar issues, or able to provide any guidance to fix this issue?

...

I have exactly the same issue on a MBP15. Interestingly, it does not occur on a 2016 MBP13-no-TouchBar.

I did all the usual stuff - NVRAM/SMC reset... tried different cabled, but the only cable which works with the LG27UD88 I have found is the one LG supplied.

No solution yet - when I have the MBP15 connected, I keep the lid open all the time.
Peter