Possible fix (or at least temporary bandaid) for faulty Atrix 4G digitizers.
I found a simple solution to fixing a digitizer that's starting to go bad, after having replaced the digitizer on my phone TWICE. The first digitizer started having the typical symptoms, where about a 1cm bar about a third of the way down the screen just wouldn't register touches. And if it did, it normally ended up with spontaneous, erratic behavior. I ordered a replacement, which turned out to be worse than the original digitizer. Sent that one back, got another digitizer, and it worked great for about a month. Then I started having same issues all over again. (And if anybody here has replaced a digitizer on this phone already, you probably understand how painful it can be.)
So, for those of you who haven't ordered a replacement yet, and are having the issues I've described above, try this test first. When you start experiencing erratic behavior and dead spots, squeeze the upper portion of the phone, where the camera, speaker, and Motorola logo is, moving in left to right. Don't be afraid to use a good amount of pressure, but don't squeeze to where you might crack something. If the problem disappears, the thin cable underneath that area is starting to separate away from the connections. (Don't know the correct terminology here.) Now, I'm not sure if it's just glue or really thin amount of solder holding these connections together, but I do know that they break pretty easily. I ended up using a heat gun, and heating up the upper portion of the phone till it was a little too hot to touch (be careful, though, too hot, and you might cause some damage to the LCD screen.) and used a rag and squeezed from the center, moving outwards, maintaining as much constant pressure as I could, till the phone was about normal temperature.
It's been roughly an hour since I've tried this, and I haven't had any issues thus far, except for a couple hiccups. I may end up doubling up on the double sided tape on the bottom, to create more of an incline to prevent the ribbon from further separating. But this may help squeeze some more life out of the digitizer. Hopefully this helps a few of you! :-)
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