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Newfiejudd

macrumors regular
Original poster
Jul 8, 2010
222
29
I had the awful issue of the screen being stuck at 50-75% brightness with all auto dimming functions off. Went to restore from a time machine and system locked up and rebooted. And now I no longer have a working system. As I’m travelling for business I will swing by the Apple store. Maybe a simple USB installer can fix this, any suggestions on a fix or is my system is toast?

My System display is still really dull in comparison to other 14" displays from the apple store yesterday. Is here a proper way to really reset the NVRAM on the M1 systems. Would anyone with a 14" Pro be willing to run in terminal nvram -p command and look for the display brightness level while at full brightness. My NVRAm indicates

backlight-nits 0x012c0000 - although the system seems to be at bout 80% of what it should be at full brightness.
 

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What auto-dimming functions are off? Sometimes auto-brightness makes a screen brighter.

Did you get your machine to work, then, at its reduced brightness?
 
What auto-dimming functions are off? Sometimes auto-brightness makes a screen brighter.

Did you get your machine to work, then, at its reduced brightness?
All Auto dimming functions are off. I have a ticket into Apple although they couldn't pinpoint the issue. The system was corrected from the boot issue, although the Display is just dim. I would assume this system will be replaced if Apple support can't provide a solution. It's disappointing as the issue is software related as in HDR video you will see the display increase in the areas where it should and overall. It's just dim while working on the desktop, jump to a full screen HDR video and it's perfect and bright once again, back to desktop and it goes dim.
 
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Glad the boot issue was fixed. Did the Apple Store agree the screen wasn't normally bright when you showed it to them?

HDR should be up to three times brighter than SDR.

I don't know what you mean by auto-dimming functions. Are Night Shift and True Tone off? They can make the screen look less bright.

If you think it's software related, are you running something that would affect screen brightness?
 
just go to battery settings, make sure your battery saving 'slightly dim screen when on battery' is not turned on. Took me a while to solve it also!
 
just go to battery settings, make sure your battery saving 'slightly dim screen when on battery' is not turned on. Took me a while to solve it also!
That's turned off. Apple support can't figure it out either. We all agree it's a system setting issue. We tried a re-image and nothing has corrected it. I will say the re-image was extremely fast to complete. Less than 15 minutes from 13" M1 pro to my 14.
The issues remains that there is no way to force a PRAM or NVRAM reset similar to the Intel systems. Essentially the system should reset itself on shutdown if it detects issues (not on restart). Unfortunately mine will not reset itself as it detects there are no issues. Terminal commands will no longer be able to do this function.
 
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