Microwave not heating can be several things that are internal & without the correct knowledge & test equipment you will not find the problem. Also, microwave ovens run on very high voltage electricity with parts that remain live with enough power to kill even after power plug is removed from wall. Do not remove the cover & touch anything inside. Take it to a repair shop.
Lincoln Appliance NZ
November 2008
Automatic Answer
We may have found other answers which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix microwaves.