I cant change my display's brightness

[Vector]

I had turned the brightness on my display down last night and now the f14 and f15 keys won't let me adjust it back. I thought i could do it in the preferences, but i cannot find a way. The display preferences menu doesnt let me adjust anything but the resolution and the color profile. Is there another way to adjust brightness besides the keyboard.

[jsw]

Odd... I have a Brightness slider under the "Resolutions:" list on my panel, but I've got a flat-screen ADC display (20"), so maybe that's why. Same for my iMac, but it's a smaller 17" display. Still, though, brightness sliders on each.

What display type do you have?

[Vector]

I have a 17in ADC flat-screen. Here is a picture of my displays window:

[jsw]

<never mind... was asking if it was a laptop>

[Vector]

it is a 933 mhz g4 quicksilver. the only function key settings i am using are the f1-f7 keys for apps and the f9-f11 keys for expose.

[wrldwzrd89]

I have a 17in ADC flat-screen. Here is a picture of my displays window:
That's very odd. Your brightness control is gone completely. My display preference pane has a brightness control too:

[jsw]

Man, that is very odd.

Gotta run now, but I'll be back in a few hours. My only default suggestion is to run Applications->Utilities->Disk Utility, select your hard disk, run "Repair Permissions", then reboot.

Sometimes goofy things happen. Probably, a preference file is messed up. However, off-hand, I'm not sure which one stores the display prefs.

[Vector]

ok i will try that. thanks.

[jsw]

I'm leaving now...but one last thing: do you have AppleCare? This is definitely something to call about...

[Vector]

no, i dont have applecare. i tried repairing permissions and it did not help.

[Coolvirus007]

Doesn't your display have a brightness control thing - assuming that the display is by apple. My 22" has these controls.

i think only laptops have the brightness control in the display panel because my powermac doesn't as well.

[jsw]

Another suggestion (connected using cell phone's Bluetooth and old PB with dying battery while in a parking lot, so this is likely my only post prior to returning home in a few hours):

Try going into the Color tab in the Displays pref. If you calibrate the display and use the advanced prefs, you should be able to adjust the brightness at least somewhat that way - it's a crappy substitute, but at least it'll temporarily improve your situation until someone canprovide better help.

My 'old' 20" has a brightness control right on the display (as well as a power touch button). Does the 17"? Looks like the brighness circle icon, and should be in the lower left corner of the display. I don't think it has one, but I'm not sure.

Final question: do you have any spare CRT's to hook up temporarily? That might trigger a prefs refresh and help out.

Sorry I don't know of anything else right now.

[jsw]

The display prefs are in the com.apple.windowserver.plist file in Library->Preferences on your main drive, as well as (sometimes? always?) in a similarly named file within user account Library->Preferences folders. However, as far as I can tell, the display brightness is not stored here. Might be hardwired somehow. I suppose it's possible that your display has failed in some way. It's more likely that it's a software screw up, but it might be a hardware issue.

Any way to either try your display on another Mac or try another display on yours? I suppose it's possible that just unplugging the monitor and plugging it back in (presumably with the mac powered down but plugged in) might help.

[zoetropeuk]

I had the same thing happen twice. The first time a pin on the graphics card was bent. The second time was when I was using the ADC - DVI adapater and the USB lead from the adapter wasn't pluggin in.

[Vector]

ok, i will try these suggestions. I dont think its a hardware problem simply because i haven't adjusted anything recently and it was working fine last night. I installed a fresh copy of panther onto one of my ipods and booted from it, but still no brightness slider in the preferences. I tried unplugging it earlier, but it didnt seem to help.

I have a 17in LCD display with the touch sensitive brightness button that should bring up the display preferences, but it doesn't.

I dont have a dvi adapter to connect it to either of my laptops, and i don't have another computer that uses adc connection. I have a crt, but i think i would rather endur this for a little while longer before having to haul it out and find a place for it on my desk.

[jsw]

I'm guessing that, if booting into a fresh copy of Panther doesn't find a brightness setting, then it's much more likely that it's a hardware issue. Not guaranteed, but it sure sounds like it. Best of luck!

[Vector]

I have examined the connectors for the adc cord and the video car and nothing seems to be wrong. I trashed the preferences, but still nothing.

JSW - Are you using 10.3.4?

[jsw]

Yup. 10.3.4.

[unixkid]

all u need to do is unplug the display and plug it back in.. OS X will see it and set it up appropriately. if that doesn't work then take it to the apple store and they should replace it.

[jsw]

I have a 17in LCD display with the touch sensitive brightness button that should bring up the display preferences, but it doesn't.

If you open System Preferences (if it's already open, close it and reopen it) and hold down Command-Shift when pressing the Display icon, you should get a hidden third panel that allows you to enable/disable the touch screen buttons. Is it enabled? Just curious. You might want to toggle the setting (i.e., diable if enabled, enable if disabled) to see if that helps.

Note that sometimes you need to quit and restart System Prefs a few times before this works.

[Vector]

i read that on apples site, but i have tried it about a dozen times now and it doesn't seem to work for me.

I have just about come to the point where i might have to do a clean install, but first i have to find some way to back up all of my information.

[jsw]

Are you anywhere near an Apple Store? You could at least take it in and see if one of the Macs there "sees" it correctly. If not, no need to do a clean install, 'cause the display's the problem.

[Vector]

No, i am not near an apple store. When i tried to boot with my ipod earlier, i noticed that somehow it was using the same sleep settings as my hard drive, so it may have somehow compied over some settings.

THe only reason that i have left to not think its hardware is that i have no brightness control in the preferences which i should have even if the screen is the problem.

[jsw]

If you're going to do a clean install, you might as well try to reset the PMU first. It can't hurt.

[Vector]

I tried resetting the PMU and the PRAM and neither has helped. I am going to order one of those 80gb Lacie firewire drives to transfer all of my stuff to. If i still cant get it working after that i will just have to think of something else.

If you think of anything else please tell me.

Thanks for your help

[tummee]

New to this forum. Greetings all. Signed up because I came across this thread from a Google search.

I, too, Vector, have the same issue.

I'm running an AGP G4 400 with 10.3.4. Attached is a 17" LCD Apple Studio Display, connected to an ATI Rage 128 Pro Video Card (OEM) via an Apple ADC to DVI adapter.

My problem, along with having no Brightness Slider in the Display Pane (no 'Detect Displays' button either), is that I also cannot run any peripherals through the LCD's USB hub, and the buttons on the front of the LCD do not power up the machine, prompt the Display Pane in Sys Prefs, or bring up the Restart/Sleep/Cancel/Shutdown menu.

The LCD is not the problem. It was acquired through a friend who has offered much help. The Adapter is not the issue. The ADC to DVI adapter was bought second-hand, so I bought another ADC to DVI adapter to verify that it was not the culprit. The friend that provided me with the LCD did not pass on the Install Software, because has said that 10.3.4 should have all the drivers native. This has been confirmed via research.

I'm guessing my issue, maybe yours, is the video card. An Apple Rep at CompUSA (bad place for advice, I know) at first suggested the monitor was at fault. Not a chance, as my friend would not sell me a lemon. His second guess was the video card.

The aforementioned friend is now providing me with the copies of the Install Software for the LCD. Yet, I hesitate to do anything, as he has said that Apple no longer sells the original LCDs with Installers - that 10.3 has all of this native. Real plug-and-play. Friend says I run the risk of really messing things up if I go dropping old drivers in the pot.

I'm all for popping a new video card in this machine (a decent investment) if I can be sure that this is not a software issue. The LCD is awesome, if a bit bright... I have created a display profile with an adjusted Gamma that makes it easier on the eyes. I just don't want to sink my OS so I can have full functionality of my display.

Any help from the community would be greatly appreciated!