Galaxy A50 - Screen Wake-up Issue issue.

[Android Central Question]

Hi,
My screen was cracked and I have replaced with an original A50 screen. When I turned it on the phone booted correctly and worked fine but when it went to sleep after 30 seconds (default time) of inactivity it will not wake-up even after pressing power key or tapping the screen (motion and gesture settings are correct) but the phone was internally working. When some one call the phone it rings but screen does not light-up (it does not wake-up) and I cannot pickup the phone.

The only way to restart the device is to press volume down + power key (soft reset). I also tied to factory reset and also flashed the phone but did not solve the problem. The volume keys works if audio or video is playing. The power key also works as it puts the phone to sleep mode after pressing it.

The only thing is not popping up is the ringer volume pop-up (slider) when I press volume up or down key to reduce or increase the ringer volume from home screen.

Please help.

Thanks in advance.

 

[mustang7757]

How long ago you got screen replacement? Maybe contact them ?

I'll leave a Link to register so you can communicate here as a guest account you can only post questions but can't reply.
https://forums.androidcentral.com/showthread.php?t=409154

 

[LondonTown1]

Started happening immediately after screen replacement.
The contacts seems to be okay as volume up and down buttons are working. The power button is also working.
When the phone is in sleep mode and if someone calls the phone rings but the screen will not wake-up and I cannot see who is calling because screen is black and cannot pick the phone.

 

[mustang7757]

Hi, welcome!

How long ago you got it replaced?

 

[LondonTown1]

A week ago.

 

[mustang7757]

Go back and explain to them the situation , something they did not right.

 

[LondonTown1]

I have replaced it myself.

 

[mustang7757]

I have replaced it myself.

Oh !
Double check your work , possible defect screen if you went for cheaper option.

 

[LondonTown1]

Screen is OEM. I am opening it again to ensure that all is well..

 

[mustang7757]

Screen is OEM. I am opening it again to ensure that all is well..

Ok , by the way you have done this before or first time ?

 

[LondonTown1]

I have replaced the screen before for another phone successfully... therefore I have done it for this one..

 

[mustang7757]

I have replaced the screen before for another phone successfully... therefore I have done it for this one..

Ok , yeah so just take it back apart look around , maybe use a magnifying glass to see as little parts in there .

 

[VidJunky]

The screen only comes on when you initially power on the phone. If the screen times out or you put it to sleep with the power button it will not light again. It seems to function correctly when it is awake....

Power on the device and with the screen awake press and hold the power button until the power off/airplane mode/restart buttons appear. Note where they are on the screen, I'd say aim for the restart button. Put the screen to sleep. Press and hold the power button long enough that those buttons would appear and press in the area of the restart button. You may have to press twice, on my device I have to confirm that I want it to restart. Then see if it restarts. This would confirm that the screen is actually working.

I have a feeling the screen is awake and the backlight isn't coming on. Without the backlight the screen will appear dark enough that you really can't read or see anything on the screen. You could try without restarting it to shine a light on the screen at an angle but I'm not sure if that would work.

If the backlight isn't coming on it could be an issue with the light sensor or a defective screen. Granted it is an OEM part but it was likely from a damaged unit and their test before selling it was just to see if it turns on, which it does but that doesn't make it a good part. If you're able to confirm that it is the backlight you may have grounds for a return or exchange. If the screen wasn't acting normally when it was on, I might think that one of the connections wasn't properly plugged in, or wasn't fully engaged, but everything works when it's lit. That seems to point to a defective part.

 

[LondonTown1]

Thank you. I will try this and update you after I re-assemble the phone.

 

[LondonTown1]

I reassembled and tried what VidJunky suggested but no change. So, the screen seems to be okay. Next day, I have opened it again and to double check on everything but no luck so I gave up and assembled it back still same issue. I also took it to a shop and they checked on everything and said that they have not seen such an issue and cannot fix.

Next morning it was on the table and I moved it to make some room and noticed the screen lit up and it stated working... I have no idea why.

Though it is not a solution but wanted to have a closure to the thread as many people do not come back after getting help from the forum. I want to Thank VidJunky and mustang7757 for their help and guidance.

 

[mustang7757]

I reassembled and tried what VidJunky suggested but no change. So, the screen seems to be okay. Next day, I have opened it again and to double check on everything but no luck so I gave up and assembled it back still same issue. I also took it to a shop and they checked on everything and said that they have not seen such an issue and cannot fix.

Next morning it was on the table and I moved it to make some room and noticed the screen lit up and it stated working... I have no idea why.

Though it is not a solution but wanted to have a closure to the thread as many people do not come back after getting help from the forum. I want to Thank VidJunky and mustang7757 for their help and guidance.

Thank you you for giving us the update , hope to see you around, your welcome!

 

[MateuszZ]

I reassembled and tried what VidJunky suggested but no change. So, the screen seems to be okay. Next day, I have opened it again and to double check on everything but no luck so I gave up and assembled it back still same issue. I also took it to a shop and they checked on everything and said that they have not seen such an issue and cannot fix.

Next morning it was on the table and I moved it to make some room and noticed the screen lit up and it stated working... I have no idea why.

Though it is not a solution but wanted to have a closure to the thread as many people do not come back after getting help from the forum. I want to Thank VidJunky and mustang7757 for their help and guidance.

Your issue is the main flex cable. You probably figured that out or replaced your phone by now, but ill just write it to anyone struggling with the same, very uncommon issue.