By taking it to a repair shop. Very dangerous to try & repair it yourself even if you had the knowledge & the test equipment. It runs on very high voltage electricity & is capable of killing you even after power is turned off.
Lincoln Appliance NZ
November 2009
I can answer this question...
how to fix a microwave that still works but doesnt heat up ?
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix microwaves.