Microwave will not heat and displays H97 shortly after starting a cook cycle.

Safety first: Unplug the microwave. The inverter and magnetron operate at lethal voltages. Do not attempt live testing unless you are a trained technician.

• Basic reset: Disconnect power for 10–15 minutes, then reconnect and test. If H97 reappears immediately, suspect the inverter or magnetron.
• Listen and observe: When starting a cycle, note if you hear the usual hum. A brief hum then shutdown with H97 often indicates inverter protection.
• Visual inspection: Remove the outer cabinet and inspect the inverter board and magnetron area for burnt components, arcing marks, or melted connectors.
• Check cooling: Ensure the cooling fan is operating and vents are clear; overheating can trigger inverter faults.
• Component replacement: In most cases, H97 requires replacement of the inverter power board and sometimes the magnetron. These repairs should be performed by a qualified technician due to high-voltage risks.