Hi @Radhika,

Welcome to the Dyson Community! 

The motors which power Dyson cordless vacuums are engineered to pulse to warn you that something is preventing airflow from passing through the machine. They’ll then shut off for protection. 

This will usually be triggered by a blockage somewhere in the cleaner head, wand or bin inlet - the filters may also be overdue for a wash. Make sure the bin inlet flap can move freely - if it’s jammed shut, this could also cause your machine to pulse. Following the steps shown in our video support guide will help you locate and resolve any issues: 

In normal use, both filters should be washed at least once a month. Use warm water without detergent, and allow the filters to air-dry completely for at least 24-48 hours. You can place them in an airing cupboard, by a radiator, or on a sunny window sill to help them dry:

Hope this helps! If you need further support after you’ve followed all of these steps, please get in touch with our experts via Live Chat through our Digital Assistant. Once you’ve clicked the round purple button on Dyson.com you can start a conversation with an agent by clicking the agent icon at the bottom left of the chat window.