display backlite replacement instructions
do you sell the backlite? do you have the replacement instructions? FOR THE POWERBOOK G4 15" ALM
Before you start replacing parts, please hook your Mac up to an external monitor and tell us what you get. I am not convinced that your problem is the backlights. Here are the symptoms of defective backlights:
Defective CCFL backlight may have the following symptoms: Screen flashes on red/pink and goes off. Picture stays on in red and slowly be come normal. Picture flickering with dim display. Picture flickering on and off. All these symptoms indicate that the LCD backlight lamp (CCFL Lamp) has reached the end of its life.