The HTC EVO 3D is an Android smartphone developed by HTC released exclusively in the United States through Sprint.

11 Questions View all

Replaced digitizer, now the LCD Isn't working.

A friend of mine replaced the digitizer in his HTC Evo 3D, but when he powered it on the LCD wasn't working (as seen in picture) but the phone seems responsive with sound Ect. So i doubled checked all the ribbon cables and they were fine, so i'm assuming it may have something to do with the LCD.

Has anyone else had this issue or knows how to fix it?

Block Image

Answered! View the answer I have this problem too

Is this a good question?

Score 0
Add a comment

3 Answers

Chosen Solution

Yes this tends to be an issue after removing any LCD and reinserting it in small devices such as an iPod or phone. 99/100 times this is fixed by turning the device on and off as the LCD isn't actually damaged it just needs resetting. If this does not work then try it again just to be safe. If you still get nothing then remove the battery and reinsert it. If still nothing then the LCD or the Logic Board has been damaged during the repair, with any luck the LCD is to blame.

Post back with the results and I'll give you another suggestion but chances are the reset will work :)

Was this answer helpful?

Score 0

Comments:

Tried powering off, plus pulling out the battery, neither of those worked,

what was your other suggestion?

by

It looks to me like the ribbon cable has been damaged during the repair. It could possibly be that the cable is not seated in it's connector correctly. Before we proclaim that the LCD is damaged it's best to rule that out.

If you decide to do this, just get to the LCD connector and remove the flex connector and then reinsert it making sure it's seated correctly :)

If this doesn't fix the issue then it has to be a damaged LCD or Logic Board, I doubt it's the logic board but we can't rule that out just yet.

Try this and get back to me, if it works great :) If it doesn't then look at buying a replacement LCD.

by

Add a comment

the problem with these type devices is the multiprong connections where they mate to the ribbon cable end headers. The contact patches are around 10-12 for supply line connections and 30-80 or more on the logic signal headers. as the overal width of the headers on these multi conductor ribbon cables are less than 2 cm mostly, this makes the contact patches on the headers and their corresponding pin sockets freekin tiny....with the pins very close together. All it takes is a bent pin or a smudge of foreign material -conductive or non conductive to foul up the works. Non conductive foreign debris creates an open circuit, and conductive foreign debris (biological finger oils and whatnot) creates short circuits and logic errors as they cause stray logic signals to trigger gates and switches fouling up the logical works. Assuming you dont have debris contamination, and pins and headers and ribbons are all ok, its the correct path of troubleshooting to inspect very closely (good magnifier, microscopes etc) with LOTS OF LIGHT to see if circuitboard traces and solder joints have been opened (broken) or if smc components (surface mounted) have been broken or dislodged. its a literal nightmare at this scale which is the driving force in modern repair and diagnosis of these devices being relegated to an art of "swap-tronics" instead of traditional "electronics" repair. These days you "swap"assemblies and sub-assemblies carefully to diagnose or repair...not having these spares and stocks simply means you aint gonna fix it... :0)

may the force be with you -padiwan...

Was this answer helpful?

Score 0

Comments:

Yeah I tried, blowing out the jaw connector, still nothing, its really hard to find the same issue online though, that's what I'm baffled by.

by

Add a comment

I have the same issue and this just adds to the list of reasons why I hate repairing the HTC Evo 3D.

Was this answer helpful?

Score 0

Comments:

To add input about this issue. I have two devices and one works completely fine. A second one had a sporadic touch screen so I was swapping the logic board but the same screen as above happened. Now that logic board does it on both LCD screens I have but the other logic board doesn't do it on either one. I put the logic board in a 99% isopropyl alcohol bath but it did not change the situation. It looks like the issue is with the logic board unless someone else has any more input.

by

Add a comment

Add your answer

BuBuSan will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 0

Past 30 Days: 1

All Time: 1,075