Your question is in the Washing Machine category - but no matter...
Yes your microwave will have an internal fuse - take the covers off to gain access to it.
There are videos on youtube that show how to find the fuse.
Be warned that high voltages lurk inside a microwave even when it's unplugged - honestly.
Something will have caused the fuse to blow - if you just replace the fuse then that too is likely to blow.
You may do well to leave it to a professional - or buy a new microwave.
Good Luck...
March 2017
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