Display has no backlight or dark screen

This can happen if you are using a clear screen protector. Try removing it and see if the display returns. If this is your issue, it has to do with the iPhone trying to detect when people have it to their ear so it shuts the screen off. Problem is the screen protectors set it off by covering the sensor.

As described above, a screen protector can cause this and so can the wrong case. If a case is the issue keep in mind that cases made for the 1st generation and the 3g are not interchangeable.

illy5603 wrote:
This can happen if you are using a clear screen protector. Try removing it and see if the display returns. If this is your issue, it has to do with the iPhone trying to detect when people have it to their ear so it shuts the screen off. Problem is the screen protectors set it off by covering the sensor.

I just had this happen to me. I'd shut it off several times, even did a full software restore, with no effect. After searching out this topic, I decided to try peeling off my screen protector; which had been on with no problems since I bought the phone late last summer.

By the way, no change immediately; but when I shut the screen off (just a normal power button push, not a restart) and turned it on again, all was fine and the backlight was back in normal operation.

So for anyone else who sees this "unlikely" solution, yeah; give it a try.