Backlight stopped working, iBook G4

Well, if the backlight works at some angles, the cable is a likely culprit.

Usually the components involved in a faulty backlight are:

1. A worn out cable, that intermittently works, so, while "resting" may have continuity, when pinched or moved disconnects itself because of broken/pinched parts

2. A worn out inverter

3. A broken backlight.

So to rule out damages, you should attempt a cable change. If doesn't work, an inverter change, and only if it doesn't work, an LCD replacements.

Also, some expert users may replace the CCFL lamp inside the LCD, but that's a tricky, hard-to-do operation.

Your diagnosis is correct, try how it works with a better cable, if it doesn't work go for the inverter.

Thanks, guys. My backlight would go out whenever I moved the display, but I could faintly see my desktop on the screen. I took it apart and inspected the inverter cable, hoping to see obvious damage, but didn't see any. After I started to peel back the shielding on the cable, the red wire must have been worn down to a single thread because it came right out, broken about an inch down into the shielding. I replaced the cable, and all is good now!