Microwave shows E5 and stops heating, turntable and light may still operate.

Critical safety warning: High-voltage components inside a microwave can be lethal. The high-voltage capacitor can retain a dangerous charge even when unplugged. Do not attempt HV testing unless you are trained and equipped. For most users, this fault should be handled by a professional.

• Step 1 – Basic external checks: Unplug the microwave. Inspect the power cord and plug for damage. Confirm the wall outlet is properly grounded and not overloaded.
• Step 2 – Listen for abnormal sounds: When the error occurs, note if there is a loud hum, buzzing, or burning smell. These are signs of HV component failure.
• Step 3 – Do not bypass safety devices: Never bypass fuses or thermal cut-outs to "test" the unit. This is extremely dangerous.
• Step 4 – Professional service: Due to the risk, replacement of the high-voltage capacitor, diode, magnetron, or transformer in Swan microwaves should be carried out by a qualified appliance technician familiar with microwave HV systems.

Attempting DIY repair on the high-voltage circuit is not recommended.