My vacuum does not turn on

I kicked you out of computers, off topic there.

it needs service.

it's probably the on/off switch
I found a cool hint at http://www.fixya.com/support/t7785183-trying_remove hope this helps you

If it was running for a while... It may be overheating. It has a reset: http://www.ehow.com/how_5943288_reset-dyson-vacuum.html

But maybe just let it cool for an hour or two and try it again?

Check the power switch, plug cord and vacuum wiring. A open circuit will cause that and you need a continuity tester to test it. Once you find the trouble part, replace it with the same size and rating. A dent or vent wire will cause not to flow the current and voltage so check it.
Thanks for asking.

You said you checked the main breaker but did you change the fuse in the plug

Well you might want to change the fuse in the plug then make sure the cable hasnt been cut

not a expert just trying to help,, check and see if brush turn by hand,, if so take bottom plate off and check belt to see if it is broke,,hope this help you

Loose wire, bad switch, or thermal cut-out. In any event, you will have to use a voltmeter to troubleshoot the problem, there is no way of knowing the problem otherwise

Just before it shut down were you pulling on the cord? For it to shut down like that it almost sounds like the electric cord has a break in it-probably at the plug