Fourth generation iPhone. Repair is straightforward, but the front glass and LCD must be replaced as a unit. GSM / 8, 16, or 32 GB capacity / Model A1332 / Black and White.

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No Backlight with Replacement LCD


My iPhone recently had a bit of a bath which seemed to kill it. I left it in a bag with some silica crystals to dry it out for a few days. Once I tried it again, the phone did turn on but had no screen! The touch wouldn't work and showed nothing, BUT, the backlight was working. It would ring and iTunes recognised it.

I bought a replacement screen and some isopropyl alcohol (99.9%) dismantled the phone, cleaned the top of the logic board which showed some signs of corrosion, fitted the new screen and it all worked apart from the backlight. I could unlock it so backed up with iTunes, then tried it with another LCD and the same happened.

So I dismantled it all and fitted the original screen, and it worked perfectly! Touch screen, LCD, backlight, everything!

Now, the original LCD had some water marks and damage so I refitted one of the replacement screens and again, no backlight!

Is it likely that the two replacement screens I have bought, both have faulty backlights? Or that my iPhone is frying the backlights in the replacement screens as soon as they're fitted (not original Apple products)? Anybody have any experience with aftermarket screens backlights not working?

Many Thanks


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Ok, I've just discovered that turning auto brightness off and dimming the screen a lot will make it work for a while.

As soon as I turn the brightness back up the backlight shuts off, decrease it again, sleep/wake and it'll work.

Does this sound like the backlight coil/ic chip thing to anybody on here?


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replace the IC and Coil

and trace back the backlight line on board

you can get the coil and backligh IC here for iphone 4 and 4S

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repair video update

okay this is a soldering repair video on iphone 4S backlight coil

the whole soldering process is the same for iphone 4


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yes it does, my advice would be to reheat the board, just enough for the solder to make its connections, then leave for a while for the board to rest hopefully this should work, if not it could be the ic needs replacing, let me know how this goes, if it doesnt work, ill show you which ic to replace

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