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Issue with LG UltraFine 5K Display on Mojave

Having an issue with MacBook Pro 15" with Touch Bar (2016) connecting to LG UltraFine 5K Display (27MD5KA) via USB-C. Previously was working with no issues for the past year before upgrading to Mojave. Now receiving alert on MBP a minute or two after connecting stating "Cannot Use Thunderbolt Accessory" with the explanation "Connect accessory to a Thunderbolt port on this Mac." No matter which port is utilized, I receive the same alert. Laptop receives power via display and but does not detect camera, microphone, or speakers on Display. When going through System Report, under Hardware > USB > USB 3.0 Bus, the UltraFine 5K is recognized.


MBP Specs

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- MacBook Pro (15-inch, 2016)

- macOS 10.14.1

- Processor 2.9 GHz Intel Core i7

- Memory 16 GB 2133 MHz LPDDR3

- Graphics Intel HD Graphics 530 1536 MB (Built-In)

Radeon Pro 460 (PCIe)

- Thunderbolt Bus 0 & 1

Firmware Version 39.3

Link Controller Firmware Version 0.38.0


I have tried restarting, force detect displays, shutdown, unplugging everything and plugging it back in, SMC reset, PRAM reset, recovery install of Mojave, changing cables, and plugging in via adapters.


Appreciate any assistance.

MacBook Pro TouchBar and Touch ID, macOS Mojave (10.14.1)

Posted on Nov 19, 2018 2:47 PM

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1 reply

Nov 25, 2018 5:00 AM in response to webster1987

Hello, I also have problems connecting my UltraFine 5k to my Macbook Pro 13" (2018) since about two weeks.


Seems like it has to do with macOS 10.14.1


But I don't get a "Cannot Use Thunderbolt Accessory". My external display just stays black, while it charges the Macbook. After some unplugging and plugging it back in + putting Macbook to sleep a few times the display connects again. It's really annoying and I never had such problems before.


Also running latest LG Firmware (3.04) from LG Screen Manager.


MBP Specs:

----------

MacBook Pro (13-inch, 2018)

2,7 GHz Intel Core i7

16 GB 2133 MHz LPDDR3

Intel Iris Plus Graphics 655 1536 MB

macOS 10.14.1

Issue with LG UltraFine 5K Display on Mojave

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