Screen goes black at end of phone call

Apple iPhone - Screen goes black at end of phone call

I have a 3GS running iOS 4.1 and have noted that when I conclude a phone call and take the phone away from my face the screen turns black and it takes several seconds to come back to life. Meanwhile the call is still "connected" and I am consuming seconds of airtime.

Is this common?

iPhone Sensor
Do you have some kind of case or screen protector which is covering the sensors on the front? I experienced this a lot when I had a silicone case on my phone which moved during the course of my conversation. Once I switched cases, it fixed my problem.

The seconds are miniscule, but I couldn't stand still being connected sometimes for a longer than acceptable time.

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This is normal.

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I have a 3g and I have the same problem. Sometimes when I get a phone call I cannot answer it. have anyone else had this problem.

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Yes, the screen goes blank when you have the phone to your head, otherwise you would be face dialing or worse. That is the purpose of the proximity sensor.

Using seconds, possibly, depends on the call if you have to hang up or not. But not to worry, you are billed by minutes if you are with AT&T, so a second or two don't matter.