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I only have hard flooring so rarely need the brush bar turned on. I’ll be vacuuming the floor and suddenly the brush bar is on. It can happen a couple of times while vacuuming or 10+ times.
Hi, Where is the position of the brush bar control lever when this happens?
(click on image to enlarge for better viewing) Update (03/15/2018) Hi, It seems as though you may have a faulty clutch mechanism. Here is a video that shows how to access the clutch mechanism in your vacuum cleaner. Just search on Ebay for Dyson DC14 clutch assembly to find suppliers of the part