Fix Your Stuff Community Store

The April 2014 update of Apple's 13" MacBook Air features refreshed dual-core i5 and i7 processors, plus slightly increased battery performance.

313 Questions View all

Options

The brightness gauge changes, but not the brightness itself

I have a Macbook Air with brightness that doesn't change, even though I slide the brightness up and down in the Display preferences.

I also tried with the keyboard keys. The brightness icon appears and the gauge does change, but the actual brightness of the screen never responds.

What could possibly be wrong here? Logic board, inverter board, the LCD?

Block Image

Block Image

Answered! View the answer I have this problem too

Is this a good question?

Yes No
Score 0
Add a comment

1 Answer

Filter by:
Most Helpful Newest Oldest
Chosen Solution

Options

Most likely an issue with BKL_PWM not changing on the logic board (this adjusts brightness). Check R7704 resistance and check for a short on that line (C7704 or U7701 can do this). If you replace U7701 and still have the same issue, the signal to adjust brightness comes from the PCH so there is not much you can do.

Was this answer helpful?

Yes No
Score 2
Add a comment

Add your answer

Alex222 will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 1

Past 30 Days: 1

All Time: 73