If you have a dim or dark screen on your iPad device, then there is a possibility that the coil that fires up the backlight is faulty or burnt out. In order to test this you will need to disassemble your iPad 2 and access the 4R7 coil to see if this is the cause of the failure. Now if you have an iPhone 4 it has a 6R8 Coil you will need to test it to determine if this is the cause of your faulty iPhone 4 screen. Any multi-meter should do the trick. see the photo to identify the 4R7 Coil Location.
Feel free to comment below, or link to photos of your failed backlight coils. I would be glad to have some extra photos showing my readers personal success stories.
This coil is susceptible to failure if your iPad screen is damaged or broken in a fall. If the screen shorts its power connection during its replacement it will cause a surge in the 4R7 coil resulting in failure. The only way to resolve this issue is to then either replace the coil. Or the logic board on which it resides.
- Apple iPad mini Wi-Fi review (itproportal.com)