Microwave issues often range from minor inconveniences to safety concerns, usually involving the heating system or the door assembly. The most frequent complaint is the microwave runs but does not heat, which is typically caused by a failed high voltage magnetron or a blown capacitor, both of which require caution due to stored electrical charge. Turntable problems, where the plate fails to spin, ususally stem from a worn-out drive motor or a misaligned roller ring. Sparking or arcing inside the cabin is often a simple fix, caused by food splatters or a damaged waveguide cover rather than a total system failure. Additionally, faulty door interlock switches can prevent the unit from starting entirely, as a safety precaution to ensure the door is securely latched. While replacing a glass tray or light bulb is a quick DIY task, internal electrical components should generally be handled by a pro due to the high voltage, these units retain even when unplugged.