In this blog, I will describe a solution if you suddenly find out that wireless connection is not working on your Toshiba laptop running Ubuntu. This fix applies to a Toshiba Satellite to be specific but may work on other makes. While it may not fix all wireless problems, it worked in my case.
The light for wireless is not lit.
When you press Fn + F8 which is meant to switch on/off wireless, the wireless light does not come on.
You are unable to connect to the internet by wireless.
The problem could be caused by a problem in the hardware.
Switch off the computer.
Disconnect the power cable and remove the battery.
Press and hold the power button for at least 30 seconds.
Replace the battery.
Start the computer. Wireless facility should now start working.
Jason’s Computer Science Blog – » Toshiba Laptop + Ubuntu, Wireless Switch Problem http://www.jasonernst.com/2012/03/05/toshiba-laptop-ubuntu-wireless-switch-problem/