20" Aluminum iMac Brightness Changes On Its Own

[shfawaz]

I have a 20" iMac that when I start using it in the morning, I have to turn the brightness back to its highest level from the lowest level. It pretty much stays bright the whole day most of the time (sometimes if I leave the screen blanker function on and/or RSS screen saver it goes back down before the day is out and I have to turn it up again). But almost like clockwork, I have to readjust it again the next morning. Anyone know how I can set this to always stay at the highest or pre-set brightness without having to adjust it every day. This is very annoying. I've tried everything I know with no joy.

I do have the iMac automatically shutting down off every night around 2am and automatically restarting in the morning around 6am. I don't think this has anything to do with it, but I'm open to ideas or suggestions.

 

[brop52]

Stop shutting down. Put it to sleep. Other than that, I have no idea.

 

[gehrbox]

I have a 20" iMac that when I start using it in the morning, I have to turn the brightness back to its highest level from the lowest level. It pretty much stays bright the whole day most of the time (sometimes if I leave the screen blanker function on and/or RSS screen saver it goes back down before the day is out and I have to turn it up again). But almost like clockwork, I have to readjust it again the next morning. Anyone know how I can set this to always stay at the highest or pre-set brightness without having to adjust it every day. This is very annoying. I've tried everything I know with no joy.

I do have the iMac automatically shutting down off every night around 2am and automatically restarting in the morning around 6am. I don't think this has anything to do with it, but I'm open to ideas or suggestions.

If I read your post correctly you are saying that the brightness level adjustment is moving on its own. If that is correct do the following:

- Select System Preferences from the Apple menu.
- Select the Energy Saver Icon.
- Make sure "Settings for:" says "Power Adapter".
- Below that select the "Options" toggle button.
- Uncheck "Automatically reduce the brightness of the display before display sleep"

 

[maconhouse]

I am having the same exact problem on a 24" iMac, and changing the energy saver did not resolve the issue. I also have my Mac shut down each night (preference of my company). Any other thoughts to resolve this issue?

 

[maconhouse]

Sleep fixes problem

I changed my settings so that my computer doesn't restart overnight, and it remedied the problem.

I am having the same exact problem on a 24" iMac, and changing the energy saver did not resolve the issue. I also have my Mac shut down each night (preference of my company). Any other thoughts to resolve this issue?

 

[brop52]

Why would you set it to restart overnight? What do you do with it now? Put it to sleep?