M1 MBA display brightness suddenly going down on its own

[Apple_Robert]

M1 MBA base model running 11.1

A few minutes ago, I noticed that my display brightness was overly bright. I checked the setting and it was on max, which I have never done. I adjusted it and a few minutes later, I noticed that the display started slowly dimming on its own. I turned off the M1 and unplugged for 5 minutes and turned back on, and the same thing happened again. The only time the display is supposed to slightly dim is when it is on battery (per the tick option).

Since I rebooted, it is also increasing the brightness on its own as well.

Has anyone else run into this problem?

Edited to add: Found the "adjust brightness automatically" was still ticked. I thought I had turned it off when I first got my M1.

 

[mgymnop]

You are probably on auto-brightness. You can turn that off in system prefrences.

 

[Apple_Robert]

You are probably on auto-brightness. You can turn that off in system prefrences.

Thanks for the reply. I figured it out just before you posted. One of those you thought you unticked when you didn't kind of things. lol I didn't check that right away because I thought I had turned it off. Next time I won't glance over the obvious.

 

[mi7chy]

This just happened to me today. Battery was at 30% and screen brightness kept dropping near bottom. Ended up turning off default auto brightness.

 

[Apple_Robert]

This just happened to me today. Battery was at 30% and screen brightness kept dropping near bottom. Ended up turning off default auto brightness.

For several minutes, I was concerned I would have to ship my M1 to Apple. I normally don't make an easy mistake like this but, I learned my lesson. lol

 

[abhi182]

There is however something slightly off about auto-brightness on the new M1s
Auto Br used to work very well on macs.
It seems to misbehave at times on the new M1 where it will suddenly get very dim even with a minor drip in the ambient light and require manual adjustment.

I have never had a need to disable Auto Br on erstwhile macs until now.

Hopefully (and very likely) a minor software glitch that gets fixed in the next OS release cycle

 

[Zazoh]

I experienced this the other day. Was on Battery and display got very dim. Cranked it back up and it kept dropping regardless of the ambient light. Opened preferences and you could see the brightness slider moving.

Plugged in, rebooted and it hasn’t returned.

 

[LFC2020]

Auto brightness is garbage, I turn it off on all my devices.

 

[Apple_Robert]

I experienced this the other day. Was on Battery and display got very dim. Cranked it back up and it kept dropping regardless of the ambient light. Opened preferences and you could see the brightness slider moving.

Plugged in, rebooted and it hasn’t returned.

That is exactly what I was seeing. It would vacillate between 100% brightness and eventually screen off. Granted, my desk is by a window where the blind was open and the sun was setting. I thought maybe that was it but, it's never happened before so, I didn't think to check auto brightness. The ambient light was in no way changing quickly and drastically for the brightness level to go to such fast extremes on its own. Like you, I rebooted thinking that would solve it but, after a few minutes, the display brightness started visibly changing on it is own again. The way this happened makes me think there is a software bug causing this drastic change.

 

[Zazoh]

The way this happened makes me think there is a software bug causing this drastic change.

Yes. I hope it is software and not the sensor. I typically do use auto because I figure it saves a bit of battery. Unless I’m working with photos where I need a baseline brightness.

 

[Apple_Robert]

Yes. I hope it is software and not the sensor. I typically do use auto because I figure it saves a bit of battery. Unless I’m working with photos where I need a baseline brightness.

I turned auto back on as it is a partly cloudy day here this morning. I want to see if the sensor is triggered again. If it is, I will need to keep auto off for the time being as one can't work with the display doing what it wants.

If it is hardware, I have AC+.

 

[Apple_Robert]

Even though I have auto brightness turned off, I am still seeing the display brightness randomly change to a brighter setting. Sometimes this happens after a reboot, like just now, and most of times, the brightness will go to max when sidecar is engaged and a screen is moved to the iPad.

If someone else can confirm my experience, I would appreciate it.

 

[Quackers]

Even though I have auto brightness turned off, I am still seeing the display brightness randomly change to a brighter setting. Sometimes this happens after a reboot, like just now, and most of times, the brightness will go to max when sidecar is engaged and a screen is moved to the iPad.

If someone else can confirm my experience, I would appreciate it.

I'm seeing the same thing just now and again.
Auto brightness is turned off, truetone is also off.
I've been keeping my brightness set manually to about 2/3 to 3/4 and I just returned to the MBA after being away for a while and I thought it looked bright. It had gone to max brightness on its own.
I'm wondering if there's a setting I've missed.
It also happened on my M1 MBP a couple of times.

 

[Apple_Robert]

I'm seeing the same thing just now and again.
Auto brightness is turned off, truetone is also off.
I've been keeping my brightness set manually to about 2/3 to 3/4 and I just returned to the MBA after being away for a while and I thought it looked bright. It had gone to max brightness on its own.
I'm wondering if there's a setting I've missed.
It also happened on my M1 MBP a couple of times.

There is just the one setting, so far as I am aware. I like to keep mine around 8 clicks. I think it is a software bug, seeing how sidecar seems to trigger it the most.

 

[beach bum]

Even though I have auto brightness turned off, I am still seeing the display brightness randomly change to a brighter setting. Sometimes this happens after a reboot, like just now, and most of times, the brightness will go to max when sidecar is engaged and a screen is moved to the iPad.

If someone else can confirm my experience, I would appreciate it.

So far I’m not experiencing this issue, and like @Quackers, I have both auto brightness and true tone turned off.

 

[Quackers]

There is just the one setting, so far as I am aware. I like to keep mine around 8 clicks. I think it is a software bug, seeing how sidecar seems to trigger it the most.

Interesting.
Did you also turn off "slightly dim display" in the battery settings? Mine's off.

 

[Apple_Robert]

Interesting.
Did you also turn off "slightly dim display" in the battery settings? Mine's off.

Mine is still on default in that area.

 

[Apple_Robert]

So far I’m not experiencing this issue, and like @Quackers, I have both auto brightness and true tone turned off.

Always have to go against the flow don't ya, Beach. Thanks for replying.

 

[beach bum]

Always have to go against the flow don't ya, Beach. Thanks for replying.

You know me... I’m a rebel 😁. I’m hoping that this issue will be software based and not hardware. Even with AC+, it’s still a headache.

 

[Apple_Robert]

You know me... I’m a rebel ?. I’m hoping that this issue will be software based and not hardware. Even with AC+, it’s still a headache.

Edited to remove wrong information about Mac's being part of the Express Replacement Service.

I like my sidecar feature. If I find anymore bugs, I am calling Orkin.

 

[beach bum]

Oh no, not Orkin! 😂 ok, maybe not a total headache situation then, thankfully. Sidecar is a nice feature, but even with my remaining 11 IPP, it’s still inconvenient for me. I’ve never gotten used to it. Nice perks with the AC+, and even though I purchase it for each piece of gear, I haven’t had to use for any of my laptops since 2011. Did I just jinx myself? 🥺

 

[Quackers]

@Apple_Robert I just set my screen brightness to about 2/3 and rebooted. It came back on almost full brightness. A tiny bit off max. This is just the MBA screen, no monitor attached.
See if yours does the same.

 

[Apple_Robert]

@Apple_Robert I just set my screen brightness to about 2/3 and rebooted. It came back on almost full brightness. A tiny bit off max. This is just the MBA screen, no monitor attached.
See if yours does the same.

Mine has done the same several times with no screen attached. Thanks for the confirmation. Make sure and file a big report with Apple. You can access the hidden app by typing the following into the Safari browser: applefeedback://

 

[Zazoh]

I’ve only experienced once and it was on auto and on battery.

 

[Quackers]

Mine has done the same several times with no screen attached. Thanks for the confirmation. Make sure and file a big report with Apple. You can access the hidden app by typing the following into the Safari browser: applefeedback://

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