Your Dyson is blocked and is overheating. This is a safety feature. Take a look on this site: Dyson Medic, select your model and read about cleaning the filters.
Angus Black
March 2011
New switch, If you have tyo keep pressing it on, the switch is not latching correctly. New switch
Sheepdog
March 2011
I can answer this question...
Dyson won't stay on, keeps turning off after I press the start button. ?
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