Microwave displays E05 and stops cooking; may occur during longer cook cycles.
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.
Possible Causes
How to Fix / Troubleshooting
Safety Warning: Unplug the microwave before any inspection. Internal access should be limited to trained persons.
User-level checks:
- Ensure that air vents on the sides, top, and rear are not blocked by cabinets, walls, or objects.
- Clean grease and dust from vents with a soft brush and vacuum.
- Allow the microwave to cool for 30–60 minutes, then try a short cook cycle.
Technician-level checks:
- Remove the outer cover and locate the cavity temperature sensor (thermistor), usually mounted on the top or side of the cooking cavity.
- Check the thermistor connector and wiring harness for secure fit and damage.
- Measure thermistor resistance at room temperature and compare to Insignia specifications; replace if out of range or open/shorted.
- If the thermistor tests good, suspect a faulty main control board.
Persistent E05 errors after ensuring proper ventilation generally require professional diagnosis.
Repair Difficulty
Required Part
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