Published by Steve Litchfield at 16:22 UTC, August 23rd 2010
Q. I'm utterly bamboozled by the way the screen of my Nokia touchscreen phone goes black and unresponsive when I make or receive a phone call, giving me no chance of switching on speakerphone or entering tones. I've tried updating the firmware and resetting it, to no avail - the moment a call is made, the screen goes blank immediately. And then returns to normal after the call. Can you help?
A. Yes, this is thankfully an easy problem to fix and you'll need a pair of scissors(!) No, really.
What's happened is that you've almost certainly used a screen protector on the phone's delicate touch screen - a good idea, except that I'll bet that you extended the protector right up to near (or past) the earpiece. You see, there's a proximity sensor built-in, between the front camera and the light sensor, designed to deactivate the screen while you're making a call, with the touch screen presumed to be up against your face. Your plastic protector is blocking the proximity sensor's scans and making it think that the phone is constantly up against an object/face.
Simply trim the top few millimetres from the protector and reapply. It won't look as cool on the device, but I'll lay odds that the screen will now only blank when it really IS up against your face.