The motor has an overheat sensor that shuts things down when the motor gets too warm - it automatically resets again when it cools. These motors don't last forever - Dyson sell them for about £40 inc postage - but they will come out and fix your machine for £50 which includes any part - excluding filters. Check both filters - one is on the RH side of the machine looking from the front, the other is under a plastic cover below the dust drum. This one is released by prising the locating lugs apart using a screwdriver and its often forgotten.
John
January 2008
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