Enable wireless?

Hi,
I own a dell inspiron 1 525 with windows vista. My WIFI button is turned on but my WIFI light at the front is not on. However I can't access wireless networks. I ran a test which says i WLAN card is fine but says my radio is disabled. I tried pressing fn and f2 but this does not work as it doesn't have the wireless symbol on it. Also, in the mobile panel it will not let me press"turn wireless on". I have tried to connecting to the networks but they do not show. How do i mend this?
Many Thanks