macOS Sequoia 15.3 wont let me detect my second display

Can anyone help??

I've just moved to macOS Sequoia 15.3

Now my second display (thunderbolt) which worked perfectly, about 2 hours ago is now dead and cant be detected. I've looked on line and it turns out it's a common problem. I wish I had just left the upgradfe.


IS there a fix?


Thank you


iMac 27″, macOS 15.3

Posted on Jan 29, 2025 3:18 PM

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Question marked as Top-ranking reply

Posted on Jun 3, 2025 3:09 AM

Before the latest update to 15.5, I was able to fix this problem by running:


sudo rm /Library/Preferences/com.apple.windowserver.displays.plist


However, this doesn't work any more. With the help of ChatGPT I used the search described elsewhere in this thread :

sudo find / -name "*windowserver*" 2>/dev/null | tee ~/Desktop/windowserver_files.txt


The suggestion from the AI was to run:

sudo rm -f /Library/Preferences/com.apple.windowserver.displays.plist \
  /System/Volumes/Data/Library/Preferences/com.apple.windowserver.displays.plist \
  ~/Library/Preferences/ByHost/com.apple.windowserver.displays*.plist \
  ~/Library/Containers/*/Data/Library/Preferences/ByHost/com.apple.windowserver.displays*.plist \



GPT: "Yes, it’s very likely macOS now references or prioritizes:

  • /System/Volumes/Data/...
  • User-scoped container directories (~/Library/Containers/...)
  • Possibly multiple copies under specific ByHost UUIDs (try clearing all you find)."


Then shutdown:

sudo shutdown -r now


This worked for me. It looks like the displays.plist is now in a different location after the update, but I haven't bothered to work out exactly where yet. - This narrows it down a bit though. I hope this helps someone else, it's a really frustrating problem that has cost me a few days work over the last year.

173 replies

Feb 14, 2025 4:03 AM in response to WozaMAC

Saw 15.3.1 appear last evening and IMMEDIATELY tried to put this on. I have tried many of the "solutions" even knowing it was DEFINITELY 15.3 that is the cause.


Unfortunately this version did not address this issue for me and it persists. Hoping Apple can get this fixed as it is simply annoying to have to cycle one monitor every time I sit at the machine after a break. Definitely ruins the experience they strive so hard to present!

Feb 16, 2025 2:12 PM in response to WozaMAC

Having a similar issue. After the update my m4 mac cannot recognize my LG c3 tv. My tv recognizes the mac (the hdmi port says "apple" for the hdmi detection) but mac cannot recognize the TV as a display. the "detect displays" trick did not work nor did deleting the plist


I have also tried multiple HDMI cables. Although - the cables i had been using worked fine until the update completed...


The best I can get is -- sometimes -- the monitor displays "choose to mirror or extend display from the [ ] menu. but the TV still does not appear as a display


this is very frustrating. i have tried plugging it in directly and via a dongle


I updated my M1 to 15.3 and it still works fine with the LG tv...

Feb 19, 2025 3:26 PM in response to Servant of Cats

Servant,

Thanks. It appears Apple does monitor these inquiries, as you appear to mimic the very thing I was told yesterday when I spoke with "Support."


I'm probably betraying my ignorance of such things, but it sounds as if Apple made some changes in the Sequoia OS preventing or inhibiting a further "work around", as you put it. A few suggestions: (1) rather than making "work arounds" required, you might try "work withs"; (2) an explanation of why the old OS worked and the new one does not might go further toward customer satisfaction and understanding than an attitude of what Apple did or did not promise; and (3) pointing the finger elsewhere is never a good strategy in seeking continued patronage.


As this site appears to attest, there are a lot of customers like myself who rely on multiple screens.. I would think the good folks at Apple would look for ways to accommodate those with this need in the design of their OS, rather than prevent it.


Thanks Servant.

Feb 19, 2025 5:02 PM in response to RetiredLegalBeagle

Retired,

I don’t work for Apple.


The M1 iMac’s Technical Specifications were readily available before you bought it.


In addition, an examination of the Technical Specifications of all Macs that use plain M1 chips shows a consistent pattern. None of them support more than two displays, total, where the built-in displays on iMacs and on Mac notebooks count towards that limit.


If the plain M1 chip only has two display generators (as all evidence suggests), there is no macOS change that Apple could make to provide more first-class hardware-supported display outputs on Macs that use that chip.

Feb 19, 2025 5:09 PM in response to Servant of Cats

That's all great. I have an M1 Pro MacBook and it had the problem. If you read this thread, you'll see that the majority of people posting have had a MacBook setup with multiple monitors on 15.2, and the setup worked. Your argument is about the nature of the bare-metal M1 CPU, and it is correct. It is also not relevant to this conversation, for obvious reasons: if people's MacBooks supported their monitors before with their CPU native abilities, they should continue to do so under 15.3.

Feb 19, 2025 7:40 PM in response to Servant of Cats

Servant,

I am well aware of the technical specs on the M1 and have been for some time. I was aware that the specs purported to limit one to two displays, the iMac display and one external.


I researched the matter and discovered that despite that spec it was possible with a Satechi Thunderbolt DisplayLink docking station to run two external monitors. I bought the docking station and did in fact run three displays at once. This would seem to suggest that, at least when running Sonoma the M1 chip was up to the task, despite the specs you reference, of running three display monitors.


You appear knowledgeable; I would appreciate your insight. Why is it that an iMac M1 running the Sonoma OS was capable of generating three displays through a docking station, but the very same computer running the Sequoia OS cannot. I'm not a techie, but it seems logical that something changed and the only thing that changed was the OS. If Sonoma could provide three screens, why can't Sequoia?


Unless Apple wants to for some reason discourage use of docking stations.


Appreciate your time and your expertise.

Feb 19, 2025 8:52 PM in response to WozaMAC

Has anyone found the fix yet? After connecting the macbook it just gives a black screen

I have a Macbook Pro M3 with MacOS 15.3.1

External monitor is LG LG 27UP650-W 4K HDR monitor

  1. Tried a new HDMI to HDMI cable, did not work - infact the cable you get with the monitor is working with my other mac running on macOS 15.2 (INDICATING SOMETHING IS DEFINITELY WRONG WITH 15.3.1 update!!)
  2. Tried switching from HDMI1 to HDMI2, still gives a black screen
  3. Tried deleting .plist file from preferences and restart mac, still same issue (new file gets created as soon as I plug the HDMI cable in, but the result is still the black screen)
  4. Tried unplugging EVERYTHING and PLUG IN again, still the same black screen


I am almost sure now its not a hardware issue - be it the cable, the monitor, or macbook HDMI port, because its working when I connect to a TV, this issue is only happening with the monitor

Everything works as expected when I connect it with my personal Macbook Pro with M1 Pro chip and MacOS 15.2


Please help :(

Feb 20, 2025 6:29 PM in response to RetiredLegalBeagle

RetiredLegalBeagle wrote:

Servant

I apologize if I was rude. Thank you for your help.


I wasn't saying that you were being rude. I was suggesting that you start a new thread.


Your issue is different from that of others in this thread. Hardware-supported video and Displaylink-based video work in different ways. It is not clear whether a single Sequoia change is related to both issues – or if there were separate changes, one of which affected hardware-supported video, the other of which affected DisplayLink.


For the benefit of the people who are discussing issues with hardware-supported video in this thread, any further DisplayLink conversation should probably move to its own thread.

Feb 28, 2025 6:07 PM in response to WozaMAC

Same problem for me. I’ve tried all the fixes in this page and nothing has worked. It’s taken me 3hrs.


Thats 3hrs away from study for my final exam.

I’ve given up. Im going back to my study with the limitations of only one decent sized screen. So disappointing that Apple refused to allow us to work with more than one reasonable sized screen. Am convinced that this update & subsequent problems are all part of Apple’s need to make us do things their way.


Thanks for nothing Apple 🥺

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macOS Sequoia 15.3 wont let me detect my second display

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