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scouser75

macrumors 68030
Original poster
Oct 7, 2008
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Guys, when I unlocked m6 16" MBP M1, all of a sudden the screen brightness was very dim - almost to the bottom of the setting.

I checked the auto brightness setting and it was on. I then checked if auto brightness was working by lowering the brightness again and toggling off and on the setting, but it no longer works.

Any suggestions please?
 

scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
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Thank you Svetlin. The restart fixed the issue, but then the issue reappeared later on. It seems to be intermittent. The Ventura update hasn't fixed it either. I'm going to see how it goes over the next few days and then if it persists get it looked at.
 
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eddie78

Suspended
Sep 27, 2022
9
5
Hey there, it sounds like you're having trouble with the screen brightness on your 16" MacBook Pro M1. I understand how frustrating that can be, especially when you've already checked the auto-brightness setting and it's turned on.

I suggest you to try some troubleshooting steps that might help resolve the issue. First, try restarting your MacBook Pro to see if that resolves the problem. Then, double-check the settings to make sure that auto-brightness is turned on and that the ambient light sensor is working properly.

You can also try resetting the NVRAM/PRAM and check the power settings make sure your MacBook Pro is set to "Better performance" and not "Battery saver."

If none of these steps work, you might want to consider contacting Apple support or an authorized service provider for further assistance. They'll be able to diagnose the problem and provide a resolution.

In the meantime, you can try adjusting the brightness manually to see if that helps. I hope this helps and that you get your screen brightness issue resolved soon. Let me know if there's anything else I can assist you with.
 
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scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
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Thanks Eddie. I've restarted the Mac but that only fixed the issue temporailly and it just returns a while later.

I've also checked the settings and the auto brightness is on.

I'll google how to reset the NVRAM and PRAM. Fingers crossed.
 

eddie78

Suspended
Sep 27, 2022
9
5
Thanks Eddie. I've restarted the Mac but that only fixed the issue temporailly and it just returns a while later.

I've also checked the settings and the auto brightness is on.

I'll google how to reset the NVRAM and PRAM. Fingers crossed.
  1. Shut down your MacBook Pro M1.
  2. Press and hold the Command + Option + P + R keys on your keyboard.
  3. Press the power button to turn on your MacBook Pro M1.
  4. Continue holding the Command + Option + P + R keys until you hear the startup sound twice.
  5. Release the keys, and your MacBook Pro M1 will continue to boot up as normal.
 
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scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
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Well, I've tried it all and every time It works fine for a while then it just goes again. I'm wondering whether it might have anything to do with me sitting directly under a Velux window? Reason is, if I turn on the lights, the screen goes slightly brighter. Turn the lights off and it goes real low.
 

scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
619
Update to this frustrating and worrying issue; the strange thing is, the auto brightness works fine in bright light, but when the sun begins to set or is cloudy, or I'm sitting where there's poor light, the screen brightness goes down so much that it's border line to the lowest point on the brightness scale and it's difficult to read or see anything on the screen. I then have to manually rise the brightness. This isn't normal, is it???
 
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diego.caraballo

macrumors 6502a
Oct 18, 2013
702
1,814
Update to this frustrating and worrying issue; the strange thing is, the auto brightness works fine in bright light, but when the sun begins to set or is cloudy, or I'm sitting where there's poor light, the screen brightness goes down so much that it's border line to the lowest point on the brightness scale and it's difficult to read or see anything on the screen. I then have to manually rise the brightness. This isn't normal, is it???
You can't reset the NVRAM neither the SMC on a Mac with Apple Silicon.
Try to run a diagnostic, if you have a faulty Ambient Light Sensor it will be detected.


If results are OK, then add a second user to your Mac and see if the issue appears as well on that account.


Screenshot 2023-01-28 at 10.16.20.png

Screenshot 2023-01-28 at 10.16.54.png
 
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scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
619
You can't reset the NVRAM neither the SMC on a Mac with Apple Silicon.
Try to run a diagnostic, if you have a faulty Ambient Light Sensor it will be detected.


If results are OK, then add a second user to your Mac and see if the issue appears as well on that account.


View attachment 2149508
View attachment 2149509
Thanks Diego. I'll do this when I'm with my Mac tomorrow. Fingers crossed all is well.
 

scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
619
You can't reset the NVRAM neither the SMC on a Mac with Apple Silicon.
Try to run a diagnostic, if you have a faulty Ambient Light Sensor it will be detected.


If results are OK, then add a second user to your Mac and see if the issue appears as well on that account.


View attachment 2149508
View attachment 2149509
I just ran the test and thankfully all came out OK. But then again, it doesn't help with the odd brightness issue in dull light conditions!

I'll monitor it over the week and see how it behaves. Thankfully I have a 2 years warranty so can always ask for it to be looked at.
 

diego.caraballo

macrumors 6502a
Oct 18, 2013
702
1,814
I just ran the test and thankfully all came out OK. But then again, it doesn't help with the odd brightness issue in dull light conditions!

I'll monitor it over the week and see how it behaves. Thankfully I have a 2 years warranty so can always ask for it to be looked at.
Remember to add a second user to the Mac and test the issue from there as well.
 
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tim1000

macrumors 6502
Sep 16, 2014
442
115
is there no way to rest the display brightness to default? once you alter the brightness how does the auto brightness function work? it will not work correct. I have been using apple notebooks since powerbooks and never has the auto brightness adjust so low.
 

xraydoc

Contributor
Oct 9, 2005
11,027
5,488
192.168.1.1
Update to this frustrating and worrying issue; the strange thing is, the auto brightness works fine in bright light, but when the sun begins to set or is cloudy, or I'm sitting where there's poor light, the screen brightness goes down so much that it's border line to the lowest point on the brightness scale and it's difficult to read or see anything on the screen. I then have to manually rise the brightness. This isn't normal, is it???
Is the camera notch obscured in any way? The light sensor is in there with the camera.

Are the windows you're sitting by polarized? I'm wondering if that's possibly an issue since you say it seems to work normally with the room lights on.

I personally leave auto-brightness off and adjust manually as I don't like it changing by itself should someone flip a light on or off.
 
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scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
619
is there no way to rest the display brightness to default? once you alter the brightness how does the auto brightness function work? it will not work correct. I have been using apple notebooks since powerbooks and never has the auto brightness adjust so low.
How do you rest the brightness?

If I alter the brightness it works ok for a while, but if I the screen saver comes on or it sleeps, when I go back to the laptop the issue is back. But it is quite random. Today it seems to be OK.
Is the camera notch obscured in any way? The light sensor is in there with the camera.

Are the windows you're sitting by polarized? I'm wondering if that's possibly an issue since you say it seems to work normally with the room lights on.

I personally leave auto-brightness off and adjust manually as I don't like it changing by itself should someone flip a light on or off.
I checked and cleaned the notch and all seems to be ok.

The window aren't polarised and are normal glass windows.

It's an odd issue.
 

scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
619
An update guys - Apple could not resolve the issue and I've now been offered a replacement. I might even receive an M2 in return 😁 🤞

Has anyone else had this issue on their M1 Pro?
 

scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
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That's brilliant. Thank you Queen6.

TBH I've setup my M1 just how I want it and really don't need the M2, so if at all possible, I'd much rather keep my M1 if it can be fixed by software. But if it's hardware, then a no brainer, I'd go for a new machine.
 

Queen6

macrumors G4
That's brilliant. Thank you Queen6.

TBH I've setup my M1 just how I want it and really don't need the M2, so if at all possible, I'd much rather keep my M1 if it can be fixed by software. But if it's hardware, then a no brainer, I'd go for a new machine.
Honestly Onyx has fixed far more than Apple has ever screwed up LOL. Have an M1 myself and feel no need to jump to M2. M3 maybe with a die shrink, equally as long as the computers perform, see no need in chasing my tail over specs...

Same sentiments as a lot of work to set up a new system. If the performance improvement made sense I'd buy, portability & battery runtime is a big factor for me. So I roll with a 13" M1 MBP until times change.

Q-6
 
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scouser75

macrumors 68030
Original poster
Oct 7, 2008
2,951
619
I'm going to try it tonight once the brats are in bed and I can concentrate.

And did you mean the battery run time is worse on the M2 than the M1? Or did I misread this?
 

Queen6

macrumors G4
I'm going to try it tonight once the brats are in bed and I can concentrate.

And did you mean the battery run time is worse on the M2 than the M1? Or did I misread this?
Dont know as dont have an M2 for comparison, likely faster, but more power demanding. The one thing I've learnt is battery runtime on a portable is system paramount or it's just dead weight...

Q-6
 
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