If the motor runs but the brushes aren't turning, there are several possible reasons:
. There is something trapped in or around the brush bar. Lie the vacuum on one side and make sure you can turn the brushes by hand. They should give some resistance when turning by hand, but the should turn.
. The belt is worn/stretched and is slipping. This is often accompanied by the smell of burning rubber.
. The belt is broken. It may still look attached to attached to the brushbar but it could be broken inside.
. The brushbar isn't inserted correctly.
REMEDY: Please follow these simple instructions to determine the cause of the fault.
Disconnect the power and allow to cool for at least an hour if you have been using it
Sit on a chair, turn the vacuum upside down and hold it between your knees:
. Undo the 3 fasteners at the positions shown in the picture below on the underside of the dyson (use a coin). Pivot the back edge of the sole plate upwards and lift off the sole plate which covers the brush bar:
. Check for any debris around the brushes that may be stopping it from turning
. Check that the brushbar is correctly inserted:
. Check that the belt is intact and tight and correctly looped over the motor spindle:
If the belt is intact and tight, the brushbar turns freely and is correctly inserted and the motor runs, then your belt is probably worn/stretched and needs replacing.
All of the other possible faults can be fixed once the sole plate is removed (Step 2). Remove any debris from the brushbar, make sure it is correctly inserted, and make sure the belt is correctly looped over both the motor spindle and brushbar.
If you need to replace the belt, please see my other post for replacing the belt on a DC07
If you have done all of the above and there is still no obvious reason why the brushbar isn't turning, please post back for further assistance
Hope this helps.