McWill Game Gear replacement LCD screen with horizontal white line of pixels?

Over the weekend I installed a new LCD screen mod kit from McWill in my Game Gear, which I bought from Dragonbox.de. It was working perfectly until just a few minutes ago-- I literally turned it off for a moment, and when I turned it back on I saw a white horizontal line going through the screen. I opened it up and looked around, and there don't seem to be any loose capacitors on the board (I recapped the whole system prior to doing the mod), and I tried blowing compressed air into the ribbon connector on the screen. Is it possible that I got a faulty kit, or is there something else I should try before contacting Dragonbox's customer support?

Here's a picture of the screen only a few minutes before the problem started.

I turned it on to take some more pictures, and that's when the line showed up. This is how the screen currently looks:

Hopefully I can get this sorted out without having to desolder the screen and send it back to Germany, although I don't have any ideas left other than it being a defect in the LCD.

 

Did you check and confirm there is a clean 5v before installing the mod? The mod could be damaged if the regulator is a bit off and giving a lot more than 5v.

Also using batteries or original AC adapter? Weak batteries and cheap 3rd party adapter may flake out.

 

Yeah, I tested the voltage before installing and it hovered right at 5v perfectly. Also, I've only ever used an official Sega AC adapter and AA batteries for power.

I've contacted Dragonbox's customer support about it. Hopefully I hear back from them soon. I would rather not have to desolder the board and send it back, but it looks like it's likely a manufacturing defect. Fortunately, I've already done the hardest parts of the mod so it'd really just be a few easy pads to desolder on the mod board, and from there it'd be a matter of waiting.

 

Same thing just happened to me, though it was the bottom line luckily. Measured stable 5v before installing. Low quality lcd:s?

 

There's bound to be a lemon once in a while, I guess. Hopefully there's no trouble getting mine replaced, because the dead line on my screen is in a spot that's quite noticeable during gameplay. I don't think this problem is common since I haven't seen anyone else complain about it, although it is likely a QC related issue.

 

You do know that you cant measure "stable 5v" with a cheap multimeter?

They will average it out and show it as stable.

 

So unless I own a $300 oscilloscope there's no way to know whether or not my Game Gear is going to fry the screen?