[nemaes]

When I dial a number, as the ringout starts, the backlight dims to zero. Unless i disconnect the call the backlight does not come back on. So during the call I cannot see anything on the screen or use the touch screen to activate the speaker or anyother function....
Any idea how this can be fixed.....

[aiharkness]

I see various solutions when I search.

Could be the proximity sensor is obstructed. See KB27934-BlackBerry smartphone touch screen goes dark during a call due to proximity sensor.

Upgrading the OS may cure the problem.

Turning on the speakerphone ($ key) and then turning it off is reported to turn the screen back on, which would be a work around.

I'm still using the OS that came installed and have not experienced this personally. I tested and the display goes off when i cover the sensor and comes back on when I uncover the sensor.

I would try a hard reset first. Then, if you can't correct it with an OS upgrade or an OS reinstallation, my advice is a warranty exchange if it is under warranty.

[nemaes]

@ aihar, that worked.....i cudn't figure out where the proximity sensor is...but then i saw the red light on top which comes on....and although there was nothing in front of it, but still it was getting activated as u mentioned. So i just wiped it clean and its ok now. that was really simple
thanks....

[aiharkness]

So wiping away a smudge or whatever did the trick? Cool!

[rambo47]

These proximity sensors are far more sensitive than we had ever thought. I'm pretty OCD about keeping my BB clean so it hasn't come up for me, but it could easily crop up under normal use. Good stuff to know.