| Sign | Likely cause | What to do |
|---|
| Loud hum without heating | Heating component or control fault | Stop use and call. |
| Sparks inside the cavity | Conductive material or cavity damage | Switch off at the controls. |
| Grinding or stationary turntable | Support, coupling or drive problem | Stop use and describe the noise. |
| Door will not close firmly | Latch or hinge damage | Leave the appliance unused. |
| Display stays blank | Power supply or control fault | Call about the loss of display. |
Several faults can produce similar symptoms, especially when a microwave runs without warming food. Inspection separates a door mechanism problem from trouble within the heating system.
During the call, say whether the lights and fan still operated when the fault appeared. Mention an existing code word for word, without running another cycle to reproduce it.