Attempting to work on appliances that have live energy sources can lead to serious bodily injury or even death. To prevent such injuries, always remove the appliance from its power source before proceeding with any diagnostic or repair work. It is also important to remember that some unplugged appliances still carry a shock hazard. Microwave Ovens in particular utilize capacitors that store enough energy to cause serious bodily injury or even death.
Attention should also be paid to other dangers that exist in the form of moving and or sharp components and pinch points.
If you are not familiar with the diagnostic tools or are not experienced in dealing with potentially hazardous work then please contact a licensed repair professional in your area.