I don't know if it has a fuse - I know little about the Dremel brand but I have had some experience of similar other brand tools. The electronics seem less than completely reliable being physically too small for the job of speed regulation, torque compensation, radio interference suppression, etc. - everything is crammed into a tiny space and the circuit board is typically on the cheap and nasty side. If there is a fuse it would typically be found on the circuit board.

Mostly the failure of such tools, in my experience, is caused by the electronics though nothing can be ruled out.

I suggest you check the mains cord using a multimeter and then check the motor and if both are OK it is fairly safe to assume the fault is circuit board related.