The vacuum cleaner was cutting out. We still tried to use it and caused damage.

When we push the trigger button, only lights go on, no sound etc.

Both website troubleshooting and call center agent recommended to replace main body and cyclone. (£105)

I thought the problem might be about electronic part only (main body) and bought just that piece. (£49)

it works now! Saved £56! Dyson should update the troubleshooting page or people should try replacing main body first before trying to replace whole cyclone and main body.