MBA Rev A Forgets Display and Keyboard Settings

[silentsage]

I have a rev. A MBA and it does two odd things.

If I set the display to full brightness, then power down and back up, the display doesn't return to full brightness. I have to go into the display preferences pane and move the slider a fraction of an inch to return to full brightness. The "adjust brightness for ambient light" and "reduce brightness on this power source" are disabled, so that isn't it.

Also, the MBA forgets the brightness setting for the keyboard when it is powered off and then on again. As best I can determine the keyboard brightness is set to a random level at power up.

I've used MacBook Pros for years, so I don't think it's anything I'm doing.

Any ideas abou this would be welcome.

 

[stoconnell]

Have you tried repairing permissions and/or resetting SMC or PRAM?

http://support.apple.com/kb/HT1411

The System Management Controller is an integrated circuit (computer chip) that is on the logic board of the computer. As the name implies, it is responsible for power management of the computer. It controls backlighting, hard disk spin down, sleep and wake, some charging aspects, trackpad control, and some input/output as it relates to the computer sleeping.

SMC:
1. Turn off MacBook Air.
2. Connect the power adapter and plug it in.
3. On the LEFT side of the keyboard (Yes, the left side only), hold down Shift, Option and Control.
4. Press the power button.
5. Wait 5 seconds, then release all keys.
6. Push power button to turn your MacBook Air back on.
7. Login, let boot fully up then shutdown.


http://support.apple.com/kb/HT1379

RAM and NVRAM:
1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.