Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Telp

macrumors 68040
Original poster
Feb 6, 2007
3,075
25
I have an ibook G4, and a couple days ago, the backlight would go on for several minutes and then off for several minutes. I decided to turn it off for a couple days to see if that would help it, and now, when i boot up, theres no back light. Everything works fine, just no backlight. Any suggestions of whats wrong or what should i do. Thanks.
 
I have an ibook G4, and a couple days ago, the backlight would go on for several minutes and then off for several minutes. I decided to turn it off for a couple days to see if that would help it, and now, when i boot up, theres no back light. Everything works fine, just no backlight. Any suggestions of whats wrong or what should i do. Thanks.

Have you reset the PMU, PRAM, etc...?

Are you sure it is the backlight? Are you able to see a very faint image of what is supposed to be on the screen? You can hold a flashlight to the back of the computer where the Apple logo is and you will see video (if it is the backlight not working).

If the backlight is not working it is either:

1. the backlight is out (very doubtful)
2. bad logic board (doubtful)
3. loose or cracked cable (possible)
4. bad inverter board (likely)
 
Have you reset the PMU, PRAM, etc...?

Are you sure it is the backlight? Are you able to see a very faint image of what is supposed to be on the screen? You can hold a flashlight to the back of the computer where the Apple logo is and you will see video (if it is the backlight not working).

If the backlight is not working it is either:

1. the backlight is out (very doubtful)
2. bad logic board (doubtful)
3. loose or cracked cable (possible)
4. bad inverter board (likely)

Yes, i can see a faint image of the screen. What would resetting the PMU and PRAM do?
 
To reset the PMU do i hold shift control option power down for five seconds, or do i just press it once, and wait five seconds before i turn it on?


Nevermind. Figured it out.
 
I have reset PRAM and PMU. Neither worked, but do remeber that the backlight went on and off for several days too. This makes me suspicious to, as was said, a loose cable. Might that be possible to fix by myself?
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.