Chosen Solution

Got an iphone 4 that was dropped in a bucket of icemelt/water, cleaned it up, no backlight. Took a known good logic board and put it in, the screen is fine. A few hours of google left me with nothing, is the backlight coil still the 6R8, and where the heck is it? Does anyone know, or have any experience with replacing it? Thanks Update

Iphone 4 has a different coil http://fonefixer.webs.com/apps/webstore/… This little monster is what you need.

By coil, do you mean a part of the driver for a CCFL backlight? The iPhone 4 actually has an LED backlight for its retina display; the individual LEDs can be seen on the third picture of this step on our teardown. It looks to me like the little two-lead ribbon cable that is soldered near the display data cable connector is the backlight cable. You might want to pull off that little piece of tape covering the solder points and test the LED array for continuity.

When the iphone 4’s get wet there are a coiuple things that usually go bad.

  1. is the backlight ic
  2. is the coil right next to it. and for the coil I have been using the coil for the Iphone 3gs with great success, and i sell it also. My user name is on my profile page [URL=http://imageshack.us/photo/my-images/137…][IMG]http://img137.imageshack.us/img137/6196/…[/IMG][/URL] Uploaded with [URL=http://imageshack.us]ImageShack.us[/URL]

The first thing any of you should do before changing the Driver IC and the coil is check the capacitors around the LCD connector. If any of these are shorted or grounding then you need to remove them one by one until the short disappears. Only if the Caps are not shorted should you start along the driver IC route as it’s tricky work and you’ll need decent tools and skills. Remeber to cover the POwer IC with silver foil before you start blasting around with a hot air gun! Best option is Infrared.

You can get the iphone 4G and 4GS backlight Coil and backlight IC chip from here

repair video update okay this is a soldering repair video on iphone 4S backlight coil but the process is the same on iphone 4 just the coil location is different, and different inductance for the coil, same shape tho. the whole soldering process is the same http://www.youtube.com/watch?v=Bsk6rg0KX…