Help Hardware question

[MacLaddy]

Hello,

So my EVO decided it didn't want to display anything except blue and pink fuzz. (see picture) It wasn't dropped at the time of malfunction, or even recently, but it has taken a good number of bumps and bruises since I've owned it.

If I give a little squeeze along the left bottom side of the screen I can occasionally get the display to come back, but it is only briefly and nothing really works. The weird thing is that the touchscreen still works. If someone calls me I can answer it just by swiping by memory the way I always would. I can even hold the power+home key and take a snapshot of the screen, but the image that is saved isn't the fuzz it is what should be there. All in all, the phone is working. Just the weird screen issue.

I cracked it open and inspected all the connections and ribbons, and everything seems fine. I obviously didn't remove the LED, because that would have trashed it and the glass, but I got to that point of inspection.

What do you folks think? Is this a ribbon issue, like a bad connection, or is the display going out?

Thanks, any information is appreciated.

Mac

 

[Rukbat]

Sounds like a connection problem, but if you open the phone you'll probably be back asking how to fix the other problems you caused.

Do yourself a favor and bring it in to a good cellphone repair shop.

 

[KingFatty]

The left bottom side of the screen corresponds to a ribbon cable, so I think you are describing classic symptoms of a loose ribbon cable connection if the problem momentarily goes away when you squeeze where that ribbon cable is located.

Look at the bottom left side of this picture, you see the copper colored cable there under the battery, which corresponds to the bottom left of the screen. There looks to be a little "u-turn" type of circuit board there on the end of the ribbon cables, maybe that's where the loose connection is? Hopefully it's just a mechanical connection that needs re-seating, but you may need to do some soldering if it's simply broken.

See: Cracking Open the HTC EVO 4G LTE - TechRepublic

 

[MacLaddy]

Spoiler

The left bottom side of the screen corresponds to a ribbon cable, so I think you are describing classic symptoms of a loose ribbon cable connection if the problem momentarily goes away when you squeeze where that ribbon cable is located.

Look at the bottom left side of this picture, you see the copper colored cable there under the battery, which corresponds to the bottom left of the screen. There looks to be a little "u-turn" type of circuit board there on the end of the ribbon cables, maybe that's where the loose connection is? Hopefully it's just a mechanical connection that needs re-seating, but you may need to do some soldering if it's simply broken.

See: Cracking Open the HTC EVO 4G LTE - TechRepublic

Thank you for the reply, KingFatty. That is exactly the type of info I was looking for.

I have actually already had this open up to this point, but I wasn't sure exactly which cable I was looking for.

If I remember correctly that copper colored cable goes underneath the heat tape and attaches to a jawbone connector. I did inspect that connection and everything seemed to be fine. However, right at that point another cable did a full u-turn and disappeared into the digitizer and screen area. This crimp, or bend in the cable, seems to be at the exact same place as where I was squeezing the screen to get it to work.

Incidentally, when I put it all back together, now even squeezing the screen doesn't get it to come back on. I am guessing that it is probably the digitizer, but I'm not certain yet. Everything I have done up to this point has been relatively simple, but changing a digitizer can get a bit more hairy.

I'm still using the phone via my bluetooth and the "Assistant" app. She is helping me blindly through the Android universe.

I will look carefully through the link you posted and write back. I may take Rukbat's advice and put it in a shop, but I still want to explore all of my options.

I'm thinking now that it may have been covered under warranty, but I have a crack in the back of my plastic case from a previous drop, and I am guessing they would see that and think the two cases were related. Either way they probably wouldn't warranty it now that I've opened it. (unless there is a way to replace the tape) Duh on me.

 

[Tre Lawrence]

Had a similar issue. HTC replaced it though.