Thanks for making contact and I'm sorry you're having difficulty.
I would suggest that this is a blockage of some kind as the pulsating is caused by a lack of airflow (the motor is protecting itself by pulsating and then ultimately cutting out).
I would recommend looking at the following video which will take you through a methodical way of checking this. The model in the video is a DC59 but applies to most cordless models: https://www.youtube.com/watch?v=fdnu4yk-5vI
Furthermore, I would check the bin inlet to make sure that the one-way door/flap is not jammed as this also can cause the problem.
If you continue to have difficulty, please give the Dyson Helpline a call on 1-866-693-9766 (US), 1-877-397-6622 (CA), 0800 298 0298 (UK). Our experts will be happy to talk you through some further diagnostic checks when you have your machine easily to hand.
Take the sole plate off the brush bar (with a coin or a screw driver)compartment and check for blockages near the brush bar and make sure the brush bar spins round freely.
Its sounds like the clutch is slipping (it does this to protect it self from burning out when something is stopping the brush bar from turning)
A quick test is when in upright position turn the brush bar knob to off
(usally in drive postion) then try the user position again - the brush bar should not be turning and they should be no noise
if it started after you cleaned the filters, it is because when you smack the filter that is in the ball like they tell you to, it pushes the gasket in so air can sneak past it. take it back out and pull the rubber gasket away from the filter so there is about 1/16-1/8" away all the way around, then put it back in. it will seal it and stop.
If you will get online with repairclinic.com type in the name of the appliance and model number. You should be able to type in the part and find exactly what you need along with the price. It normally takes from 7-10 days to get your part. I have always found them to be very reliable and they have millions of parts. I have always found the parts I needed from them. It may not be a bad idea to order an extra while you are ordering. If it is urgent you can choose an over night ship option but this will cost more. I hope this solves your problem.
fiter is dead clogged up inside. you could wash it 50 times still wont unclog. simple fix, just buy a new filter and empty bin more often in the future and wash filter every month and fit new one every two years
Apparent common failure is that either the thin yellow and or blue motor drive wires that run from the LH side of the vacuum where the "control board" is located down into the hinge / ball area become stretched and then fray and eventually break. Happened to my Dyson twice. First repaired under warranty, second took about 20 minutes. You need a Torx screwdriver to remove the LH panel ( 4 screws) and also an access panel (2 screws) at the side of the ball which permits access to the blue / yellow wire connectors. I replaced with a new wire and connectors having fed the wires through the access hole making sure sure enough wire was available for the movement of the handle. Also ensure that when the covers are replaced they do not trap any wires underneath.
Sounds like the motor is burning out.
Make sure you are not plugged up some place. Hoses etc. You need lots of suction.
Make sure your vac is not set too close to the floor. The air needs to be able to get in or it will burn out.
With the machine switched off, press the re-set switch on the side of the head, making sure you push the button in as far as you can. When you switch the machine back on and lower it into the vacuuming position, the brush bar should start turning.
If this doesn't rsolve the problem, please contact our Helpline on 0800 298 0298, between the hours of 7am - 10pm, 7 days a week.