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I have just replaced the battery in a stock IPhone SE for a client. This is the first repair for this particular phone, and the battery did not charge prior to repair. During the repair, I used parts from iFixIt and followed the guideline exactly. Upon completion, phone worked as normal, so I returned the phone. The next day, they brought it in to me and I see that the backlight works, but no display. I have disassembled the phone again and made sure all contacts for cables are secured and that nothing else is out of the ordinary, which it seems there isn’t. However, still no luck. I can feel the phone vibrate when resetting (both soft and hard reset), so I know it is actually turning on. The backlight also works, just no image on the LCD display. Any help is appreciated and any tricks will be used if available. Thank you in advance.
It’s very important to always disconnect the battery before disconnecting/reconnecting the screen assembly. The issue is that the LCD connector has pins that have high voltages (i.e. the backlight is ~20V) and ground in very close proximity. When you fumble around trying to line up the connector plug to the receptacle, you can short out the voltage rail and cause damage to the components in the backlight or LCD circuit. If you’re lucky, then only a filter is damaged but other times, the entire circuit could be affected. Either way, this type of repair requires micro-soldering and isn’t really a DIY repair. To test for this, plug your device into a charger or an iTunes enabled computer. Then shine a bright flashlight on the screen. If you can see a dim image, then the backlight circuit has been damaged. If you can’t see an image at all, then it may be the LCD circuit that is damaged. You can connect the original, cracked screen to confirm this. If the original screen has the backlight on, then the replacement screen has an issue. If the original screen also doesn’t show the backlight, then the backlight circuit is blown. If iTunes doesn’t recognized the device than the problem is more than just a screen or backlight issue.
