Fuse and door switches are a good place to start. There should be several switches or contacts located where the door hooks enter into the unit when you close it. If your door is off-center, and the door hooks are not making adequate contact, you will not get power to the unit. The fuse location is different in every model, check the wiring diagrams in the parts section for those specifics.

You can check the fuses and switches with a typical meter, guessing which switch is blown could get costly. Unfortunately i've had the same issue this weekend, only switching the power source didn't change anything. I also just finished checking all the fuses and switches I could find, still no direct problem on my end.

Good luck to you however.