E03
Wolf
Magnetron or High-Voltage Circuit Failure
Microwave runs but does not heat; display shows E03 after a short time.
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Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
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Possible Causes
Failed magnetron, Defective high-voltage transformer, Defective high-voltage diode, Open thermal cutoff in high-voltage circuit
How to Fix / Troubleshooting
Safety first: Unplug the microwave or turn off the breaker. The high-voltage system (transformer, capacitor, diode, magnetron) can store lethal voltage even when unplugged. Do not attempt internal repairs.
User-level checks:
- Confirm that the unit is not in Demo mode (if applicable to your Wolf model). Demo mode will run the fan and light without heating.
- Test with a microwave-safe cup of water for 1–2 minutes. If the water remains cold and E03 appears, heating has failed.
Service recommendation:
- E03 indicates a fault in the high-voltage or magnetron circuit. These components are not user-serviceable.
- Contact an authorized Wolf service center. The technician will test the magnetron, high-voltage transformer, diode, and thermal cutoffs and replace the defective part.
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Repair Difficulty
Professional Required
5/5
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