View Full Version : PowerBook G4 17" inverter board problem

Nov 11, 2010, 12:32 PM
Hi I have a PowerBook G4 17" 1.33Ghz with display problems.

The backlight no longer works. I can see that the screen is still displaying an image and the Mac works with an external monitor.

Whilst searching around I found that one of the pins from the logic board socket isn't supplying +5v to the inverter board. The cable is good and I have also replaced the inverter board.

I've tested the voltage of the inverter board connection socket on the logic board. This is what I get.

Pin 1 : Ground
Pin 2 : +12v
Pin 3 : 0v (ground)
Pin 4 : 0.09v Should be +5v
Pin 5 : 1v (Ranges from 0-4v to dim display)

Would it be possible for me to pull a +5v feed from elsewhere on the logic board to power the inverter and if so where would be a safe place to get it from.

My first thought was one of the fans but I don't know if this will be safe or not.

Thanks in advance for any advice