KitchenAid microwave doesn't power on

Hello,

Our KitchenAid microwave KHMS147KSS-1 doesn’t turn on. Not sure what happened, It was fine but as soon as exhaust fan button was touched, it just turned off.

I thought it could be fuse, so I opened up and replaced the fuse behind the control panel but that did not help.

Anything else I should look at? Is it better to just replace it since it is about 10 years old.

thanks in advance