June 5th, 2011, 09:13 AM
Join Date: Dec 2010
Location: Cushing, OK
Device(s): Moto Droid RAZR on VZW
HTC Desire on Alltel
Carrier: Not Provided
Thanked 12 Times in 11 Posts
This question is asked frequently. Excepting the possibility that your phone is actually broken, there are a few suggestions I can make.
First, do you have a third part case for you phone? Do you have a screen protector?
There is a small window hidden in the black border at the top left of the phone. It is perhaps 4x6mm. It is difficult to see, you may have to hold in at an angle in bright light to make it show up. It contains a little light sensor that is used to detect when the phone is being held up to your head. When you put the phone up to your face durring a call the screen is turned off to save battery and the phone "should" light back automatically when you take it away from your face. This takes up to 3 second to happen, so don't panic and start mashing buttons just hold the phone out away from you for a few seconds and wait.
There are times when this won't work however. If your standing in the dark you may have a problem. Also some screen protectors seem to interfer and should be cut back so that they don't cover the window. The biggest cause of this problem seems to be people with a third party case that covers the window. This was mostly a problem early on when the desire had just come out and manufacturers were unaware of the light sensor.