Hi
When you open the main body up you can replace the switch and motor
However this isn’t recommended as it is a long and hard process and parts aren’t very common
There aren’t many videos that I can find but most hand held dyson open the same way
What I would do it replace the whole main body as they can be had at a low price without a battery or cyclone(you can swap them over from the one you have)
But if you really want you could try and find the parts and attempt to open it but it’s up to you
Hopefully this helps
Any questions please ask
Thanks:-)