USB-C Monitor (LG Ultra-wide USB-C) not connecting after upgrading to Sequoia

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Level 1

13 points

USB-C Monitor (LG Ultra-wide USB-C) not connecting after upgrading to Sequoia

Since upgrading to Sequoia (and subsequently updating to 15.01) earlier this month I've been unable to get my Macbook Air M1 to connect/recognise to my monitor (LG Ultra-wide USB-C).

I've tried:

Different cables (including Apple USB-C cables)
Resetting the memory thing (ctrl + cmd + r after reboot)
Hard restarting the monitor with and without the Mac plugged in
Restarting my mac and the monitor w. & w/o them being connected

My mac refuses to recognise my monitor and also has trouble recognising the ORIGINAL charging cable in the USB-C ports. I hoped 15.01 would've solved this, but no dice so far.

Anything else I should try?

MacBook Air 13″, macOS 15.0

Posted on Oct 22, 2024 12:36 AM

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Answer 1

AcKris Author

Level 1

13 points

Oct 29, 2024 1:15 AM in response to James Brickley

There are no specific LG drivers for macos. And the issue is not on LG's side of things, my monitor worked fine until the update and the issue has persisted after updating to 15.1 today.

Very creatively the issue has now moved from one USB-C port to the other, so the one previously dead one works and the other doesn't. I can still not charge my macbook or get it to regocnise my monitor with the original cable (it is undamaged that is not the issue) but the cable I got with my airpods works....

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Answer 2

AcKris Author

Level 1

13 points

Oct 29, 2024 1:28 AM in response to AcKris

There are no specific LG drivers for macos. And the issue is not on LG's side of things, my monitor worked fine until the update and the issue has persisted after updating to 15.1 today.

Very creatively the issue has now moved from one USB-C port to the other, so the one previously dead one works and the other doesn't. I can still not charge my macbook or get it to regocnise my monitor with the original cable (it is undamaged that is not the issue) but the cable I got with my airpods works with charging....

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Answer 3

AcKris Author

Level 1

13 points

Oct 29, 2024 9:45 AM in response to AcKris

The saga continues. I've now bought a new USB-C USB-C cable. It can charge both ports but does not get recognized by Sequoia. I've now also tried a HDMI cable, which at first didn't take but after a restart of the mac and the screen miracously appeared.

Yet the point of using USB-C to both charge and transmit data is now completely lost... Hopefully it'll get fixed soon and I'll just have a surplus HDMI cable....

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Answer 4

Sean Al

Level 1

0 points

Nov 23, 2024 11:54 AM in response to AcKris

I have the same issue with an LG ultrafine 4K monitor. Worked perfectly with my MacAir M1 until I upgraded to Sequoia. the 15.1 version didn't solve anything. Tried all the usual, unplugging power, cables , etc... Monitor stays dead although it still charges through usb-c port. I did get an initial flash of the alert message "Do you trust this accessory" but didn't stay long enough to be able to accept. This definitely seems like an OS issue. Sometimes external flash drives do the same and won't be recognised. All was working perfectly before OS update.

Anybody have any advice?

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Answer 5

Oct 23, 2024 10:53 AM in response to AcKris

Check if your monitor has updated software for macOS:

https://www.lg.com/us/support/software-firmware-drivers

There is a macOS 15.1 coming soon, it's still beta.

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Answer 6

AcKris Author

Level 1

13 points

Oct 29, 2024 1:51 AM in response to AcKris

I've noticed when connecting both the original cable and the USB-C cable from LG that my Mac starts searching for Wi-fi connections. Maybe Sequoia is mis-labelling the connection attempt?

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