Air flow sensor

Hi,
I dunno if anyone will be able to help me with this one but considering It's a really common problem and by the sounds of things that it might happen to me again. Does anyone know what exactly goes wrong with the air flow sensor? Is it the internal components or is it just that piece of wire with what looks like some sort of resistor or semiconductor on it that actually causes the unit to fail ?

Just a long shot
Cheers,