Backlight only, no image after screen replacement

Hi all,

I have a similar problem - I've replaced my screen & digitiser and only the backlight is working, no picture. It makes the camera sound when I do a screenshot so I know the device itself is on.

The old screen was still working, but the glass was smashed hence the repair. As per online advice, I reconnected the old screen, and now I have the same trouble - the backlight is working but there is no image.

I figure this indicates I have done something to the inside. All the connectors seem to be connected properly, as I rechecked this during both assemblies.

My next step is to clean all the connectors with alcohol, and I will let you know if makes any difference, but my question is: is anybody able to please let me know the purpose of each of the two screen connectors? I'd like to know which one I need to pay particular attention to.

Thank you

Hi guys

Here is an update:

Cleaning the connectors with isopropyl alcohol didn't help, so I figured it wasn't a case of the connectors being dirty.

I took it to a professional fixer and now it works perfectly. He said I had most likely accidentally damaged the LCD ribbons on both screens (or the one I received was faulty and I had damaged the original while removing). In any case, the message was that the ribbons are super, super sensitive. Super.

Based on this info, if you're going to proceed with the fix I recommend making sure your parts are from a quality seller, are sent in rigid packaging, and you are extremely careful with the ribbons when feeding through. If your old screen still shows an image, take the same care in removal as you do in assembly (so you have something to test against).

Though there is of course definite value in taking your phone to a pro, I'm disappointed I didn't get to see what was done to it (or get the satisfaction of a successful repair). Also I have to take his word that it was the ribbons and not some trade-secret extra twist to a screw or something.

The pro expressed criticism of internet tutorials but I didn't ask why. Perhaps it is that they don't provide sufficient, emphasised warning for dangers like these..(?)

If the occasion arises in the future I would definitely attempt another fix with this knowledge. I hope this is helpful in any amount and am interested to know how others resolve the problem themselves.

Cheers

I don't buy the "fragile cable" story. I've got the same problem (backlight and sound only). I've tried the power on, home button, disconnecting the battery, etc... I replace screens for friends and family all the time. I had the opportunity to test the digitizer assembly on a different phone and it worked perfectly. The issue clearly with the phone. I hope someone figures this out!

Ok guys I had the same problem with a hot pink after replacing a new lcd on a 4s phone.The phone will not function at all no backlight at all.So I decide to try other just encase still the same result..The screens faulted out my 4s main board,so I decide to disconnect everything and leave it out for a few minutes so I can flush all the power form the main board.As I tried the second screen it work,but as I notice that there were more oil residue on the gold connector pins which connect to the main board.This maybe be the cause or the bad screen.

Try holding both buttons down until the apple shows up. The phone will hard reload, but keep your buttons held clear through it until the apple shows up.

Try holding down the power button and the home button and it will work

Update: Problem solved. After consulting a repair tech, he informed me that the part of the cable closest to the screen is very fragile. He continued to add that there's a piece of "glass" or similar inside the cable and it's likely that when I was feeding the cables through the phone body to set the screen in that I may have bent that part of the cable too far thus damaging the connection. (there was no obvious way too see that any damage occurred) This actually made a lot of sense though - cause when I tried reinstalling my previous cracked screen I ended up with the same issue. Which led me to believe that I also bent that cable too far l when installing the screen. (And I was trying to be so careful.. just didn't realize that cable was soooo fragile!)

I got a new screen and was extra careful not to move that cable too much at the base. New screen worked great. Live and Learn.

Once you did everything correctly, and only get the backlight when you power on, hold the power and home button at the same time, This will force the system to detect the new screen and start to output video to it. Hold the buttons until the apple logo appears. Make sure you do this before ordering a new screen. This will work 99.9% of the time once nothing was damaged during the repair....

Hey, so just to add my two cents, I had the exact same problem as all of you. I don't know exactly what I did to fix it, but it seemed dead, hooked it up to the old display and i got backlight and sound, then i attached it to the new one and i got backlight and sound. Tried doing home + power button and nothing, went back and hooked up the old display, this time the lcd worked and displayed the apple logo (probably from me holding power+home), I switched it to the new display and it booted up normally and made me reauthorize the phone. Maybe i tricked it into displaying on the new lcd?

4/4S isn't really an issue. It's the bracket assembly, that's the real difference for those. I just now, after many many i4/i4S repairs, got this backlight only issue. Didn't get a chance to try it, without an extra battery, the current one had no charge. But advised the customer to try the power + home button thing