Revamped version of the iPhone 3G with faster processing speeds. Repair of this device is similar to the 3G, and requires simple screwdrivers and prying tools. Model A1303 / 16 or 32 GB capacity / black or white plastic back.

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Backlight not working - what are the usual causes?

I've read oldturkey03's comments on repairing a damaged backlight.

Mine went out after some light water damage (sensor inside hasn't changed color, etc - but we know it was in some dampness). I've opened it and didn't find any damage from the water - cleaned out a lot of dust as the front/back covers don't perfectly meet any more (would replace back cover, but I think it's mostly aesthetics and now it's covered with case).

It functions just the same as before the water damage except no backlight (damage happened about 6 weeks ago). The top on/off switch already didn't work before the water damage occurred.

Can anyone comment on the likelihood of it being the LCD damaged vs the coil? I can buy the LCD -- though a bit costly (I'd get the whole assembly), and do that, but if it's more likely the coil, should I do that first?

I also don't see how to get the part for the coil. I'm fairly new to this type of small repair, but have replaced my iMac hard drive, etc.

I'm kinda counting the cost vs benefit of repairing an older phone...

Answer this question I have this problem too

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momefarley, just like any other phone that had water damage,your phone will have to be cleaned properly. You did not tell us how you cleaned it. Disassemble your iphone with the instructions on here Take your time and familiarize yourself with the instructions first. Read the comments and the notes and make sure you understand the instructions. Once you have it disassembled take a look at the attached image and identify the coil and the area around the coil. Use some sterile water and rinse the parts off to remove the scale. Then clean it with +90% isopropyl alcohol and a soft brush.. This will displace the water and stop corrosion. Use this guide to get it cleaned. It is written for a 3G but applies to your phone as well. It is okay to submerge a board in isopropyl alcohol. After that, air dry all the components. Do not forget to clean the connectors on the board as well as the cables. Then re-assemble with a new battery This is not optional but a must to avoid failure later on. Check your board for any missing or damaged component. Re-evaluate after you clean the phone. If your backlight should still not work, test the 6R8 coil. Use this video or this one and see if it is time to change that coil. Now, if a coil replacement does not resolve your issue, there is still the possibility that it is your backlight IC 109B that is giving you the trouble. That will be harder to replace and will require special tools and techniques. Of course, you would also want to try a new display assembly. Water damage is the toughest to trouble shoot and to repair. Hope this helps, good luck.

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iPhone 3GS Logic Board Image


iPhone 3GS Logic Board Replacement



iPhone Image


Repairing iPhone Liquid Damage



1 - 2 hours

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When I opened it, I couldn't see any evidence whatsoever of any water damage -- we only knew that the outside of the phone had gotten damp and that the backlight quit working. There was no scale on anything at all. I also didn't take the logic board out and turn it over -- I'm assuming one would have to do that to see what you have in your attached picture...

There WAS a good bit of dust -- and it didn't look as if it had gotten wet at all. And the little circle sensor for water had not changed color at all. So I'm not sure if it was water damage or not.........................

I'll try to get it open tomorrow -- I don't have the suction cup and small Philips at hand to open it right now.


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It's hard to say weather it's the lcd or the coil for back light

It's kinda trial and error you'll need to try a lcd to be sure

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momefarley will be eternally grateful.
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