Both of my Galaxy S3s have a problem with their proximity sensors. I make a call, put the phone to my ear, but then if I want to hang up the screen is dead and won't wake up. I cannot disconnect the call until their answering machine hangs up. If they don't have an answering machine, the call just rings and rings until I remove my battery. This is my second S3. Is there a fix for this?
I had exactly the same problem, then set the power button to end calls. But actually if you go to Dialer(keypad), go to Call Settings and untick "Turn off screen during calls".
It works, as I had this problem since I bought the phone so I think it was set to that as default, because I never even knew how to get in to Call Settings before this problem.
There is a diagnostics mode on the Samsung Galaxy S3 - There is a sensor test you can run to make sure nothing is wrong with the proximity sensor. Follow the link Diagnostics mode
This was happening to me. I found if I put my headset in, the screen would come on then I could hang up the call. I recently changed my screen protector so this may be the culprit. I changed the setting "turn screen off during calls". Hopefully, this all helps since digging for my earpiece is not very convenient.
A little late but I have solved the problem by downloading an app called Intelliscreen. Works for almost any device, just follow prompts to activate. When it asks for the apps that you want the screen to stay awake for make sure you choose the phone app. You can set the app to start automatically when you boot up your phone.
I had this issue and found that it was being caused by dust buildup under the glass in the proximity sensor and front camera area. The dust was also affecting the front camera picture quality, you could plainly see the dust covering the inside of the camera lens area.
I completely fixed both problems just with a can of compressed air. I just pulled the back of the phone off and and shot compressed air (using the small straw attachment on the air can) all around the area of the phone. I think the spot that actually got air in there was the tiny noise rejection hole on the top edge. I could visibly see the dust clear away from the camera lens.
Immediately after that the proximity sensor started working perfectly again.
Amazing, but true - use canned air to blow into the ear piece. Dust might have gotten inside the case and be blocking the proximity sensor, causing this behavior. You might even be able to see it with a magnifying glass. I saw this suggestion here - http://forums.androidcentral.com/samsung-galaxy-s4/310276-galaxy-s4-proximity-sensors-activates-but-doesnt-turn-off-2.html and wouldn't have believed it if I hadn't tried it myself and IT WORKED!!
My proximity sensor is broken. I spent 10 hours looking for app, which would prevent screen from going black during calls. After 10 hours I found this app, which finally solved my issue:
I just wanted to share and hope others will find this usefull and won't spend that much time searching as I did.