Phone vibrates and shows sign of life but shows blank screen

Hi Krystal,

So if I understand this correctly, your sister took off the old broken screen and installed a new one but the replacement screen doesn't seem to be working, right? By any chance can you see a picture if you hold a flashlight up against the screen in a dark room? If so, that would indicate a problem with the backlight circuit.

I guess the first step would be to try some of the power off/reset ideas presented on the internet like the ones given in the following video.

TCL 30 SE/XL/30/30+/306: Black Screen, Won't Turn On? FIXED! - YouTube

To be honest, I don't have a lot of confidence that this is going to help, but if it was mine I would go through this video and try all the suggestions since they don't require any further actual repairs to the phone.

Assuming you've now tried all those ideas and your phone is still not coming on, the next step is to have your sister open the phone back up and double check the screen connector. I wasn't able to find any tutorials on screen replacement for your particular model, but there's a picture of the 30 SE that is similar enough for you to identify the correct connector.

You'll want to unplug it and check it over carefully with a magnifying glass and a bright light; be sure to disconnect the battery first! You're looking for bent, broken or missing pins on both the connector on the ribbon cable and the connector on the motherboard. Sometimes bent pins can be straightened out with some fine tip tweezers, but of course broken or missing pins are more problematic.

Assuming everything looks good, take some 90% or higher concentration isopropyl (rubbing) alcohol and clean both sides of the connector. Give it a few seconds to dry then reconnect them, making sure the plug is fully seated and snapped into place. Now plug in the battery and try turning the phone on and see what happens.

If it comes on, great, you've fixed the problem and can button it up and call it a day! If not, we'll need to try and figure out if there's an issue with the replacement screen or not. Unplug the new screen and try plugging in the old one. Of course, that assumes you still have the broken one AND it's functional enough to tell if it's working. If so, and the old screen still works but the new one doesn't, then either the new one is just bad or it's possible the screen was replaced without disconnecting the battery, which can blow out the backlight giving you a dark screen. If that's the case you'll have to buy yet another screen, but this time make sure to disconnect the battery before plugging and unplugging the LCD.

So give these ideas a try then come on back and let us know what happened and what you found and we'll see if we can figure out what to do next to get your phone working again.

Well, it doesn't look like a backlight issue, but rather some kind of problem with the LCD itself. My advice for checking the connectors and trying out the old screen still holds; worst case you may have to buy another screen; most vendors will let you return them if you just plug it in to test it without actually installing it.