MacBook Pro M1 Pro issue with dual display after updating to macOS Sequoia 15.1

I made a bootable usb with mac os 15.0.1 & clean install.

No other options available .

My mac is 2.5 yrs old.

never had a problem until i updated this morning to macos 15.1.1 and my external monitor that until yesterday used to work like a charm is not even detected by my mac M1 Pro anymore...

needless to say this is overly frustrating.

[EDIT] after A LOT of restarts (turned off the external monitor as well for a couple of minutes), the external monitor started working again

First of all, you need an image. This can be downloaded from several websites - Sorry, I am on iPhone here and can’t post the links that you will find them if you really want to

Download the.PKG installer

Then install it and from your applications folder using terminal (there are scripts around, it’s not too hard but it takes a while, I almost aborted due to missing progress…), you can create a USB boot, medium

Be sure to have a time machine back up that was made on 15.0.1 otherwise it won’t work

Then reboot your Mac holding The startup key and boot Into options

Repartition Your hard drive. (completely delete)

After that reboot or select your USB boot medium and install Sequoia 15.0.1

Now you can use your Time Machine back up to restore your Mac. If you don’t have one, you have a Mac on factory settings now

So much for an ultra short info, that worked for me

Are you using an Apple adapter? Several people have reported that the problem was with the Apple adapter and that other adapters work. FWIW, I don't have one the Apple adapters, and I have used several different macs with TV of different brands (LG, Sony, Samsung), using Sonoma, and now Sequoia, and never encountered this problem, so maybe I'm lucky and the issue is with the Apple branded adapter?

Only workaround for Macbook Pro with HDMI port is to use direct HDMI cable to be connected with monitor while keeping it on charge, till Apple resolves this issue.

I have the same problem. But i found solution. You can use https://github.caffeine-app.net and when is active mac will not going into sleep mode...

Please remove power adapter first,

plug the usb-c cable or display port cable then you will see your external display will be connected.

Plug your 5 pin power adapter again for extra power.

That's why it seems to be issue with TB4 Docks. I have 2 screens connected to my dock. 1 Dell 27" 4k Screen with USB-C to Display port (this one works fine) and HDMI to HDMI on the 2nd screen, which is LG 27" 2k screen (this one flickers). Sadly, the Anker TB4 Dock only offers HDMI Out for the 2nd screen, hence I can't get around this issue.

I really hope Apple fixes this, the issue is really annoying.

I'm using Macbook Air M2 the monitor I used with usb-c in Sequoia version 15.0.1, when I updated to version 15.1.1, I can no longer use it, I seem to be connected in the displays section, but no image comes. I installed sonoma version 14.7.1 to solve the problem but it did not solve it. For now I can overcome this problem by using hdmi.

I have updated to 15.2 and the issue is not resolved. I am using Anker TB4 Docking station. After switching from HDMI to DP Cables, the issue was less present, but it is still there... extremely annoying from Apple :/

I updated to 15.3 and I'm still having the same issue with my usbc monitor. The only solution I found was using hdmi instead, but even that has started turning off and on recently. Maybe it's an issue with cable/adaptor, who knows, it happens less often than with the usbc cable.

Hs anyone else noticed that the usbc connection disconnects more often when power usage goes up? Like when I start a dev server or run units tests or something, it seems to turn off and on immediately.

Not for me, unfortunately, USB-C connection still goes black intermittently.

HDMI works without problems but I prefer the USB-C, because it charges my MB too. I have given up on Apple fixing this issue, to be honest. They don't care.

I have the exact same issue. Also with the Anker dock and with an LG external display that is connected via USB-C to HDMI. Turns off every few minutes and the issue came up right after the update to 15.1.

I also changed cables, reinstalled the dock firmware, connected the display directly to Mac, and the issue still persists... Does Apple Watch these forums, or do we need to report this somehow?

Hi again,

I persist with apple to get more support, they told me that really they don't pay attantion to the apple discussions threads, and they don't have a lot of tickets regarding issues with external displays.

After changing cable, adapter, reset SMC, PRAM, restarting and even go back to SONOMA (yes the issue for me is still in SOnoma as I came from BIG SUR) the situation is still the same, connected TV randomly siwtch off for 3 or 4 seconds.

Please guys, open a ticket to apple support in order they have more and more tickets and pay attention to us.

Regards.

Selurnatas wrote:

Updated to 15.2 today, problem not resolved.

In fact, it's worse now; before my screen went black for a few seconds, now it's 10 seconds or even longer.

How is Apple informed of this problem? Do they check the community posts or is there a way we can inform them of the issue directly?

Use the feedback page to report:

https://www.apple.com/feedback