Chosen Solution
Hello, I have searched the questions & have not come across one to match my scenario. iPhone has been thrown, (by ex gf) in otter box case but has survived with the digitizer, lcd & backlight working fine. Then one day I dropped it half a foot while trying to plug it in at work & the backlight went out. LCD & digitizer work as I can see the icons they are just annoying to use. The water damage came from putting it above the shower head for music & it dropped, (while in the otter box). Also my daughter got yogurt on the case and poured water on it to ‘clean it up’. But both times it continued to work, (backlight) Are the backlight bulbs built into the lcd and could they have been knocked loose? Is a new lcd the answer? Thanks! No water damage on board, light still comes and goes. Could this be a coil issue?
I bet you have corrosion on the LCD connector. For some reason, water is always able to get in and under that and next thing you know, no backlight. Open up the phone again, and make sure the solder points are bright silver and not black. If it were the coil, it’d be like a burnt out bulb, no intermittent issues, just out. If you have corrosion, you’re going to need to reflow the solder or touch up each individual pin with an iron.
The 6R8 coil is definitely worth investigating as this is usually the most commom cause of backlight failure after water damage. Also as Hector suggested this could be a corrosion issue. Which will need a good old touch up / reflow and a clean with 99% alcohol to remove any unwanted residue. On the positive side, neither is a difficult problem to fix :)
