On Toshiba convection microwaves, E12 appears when using convection or combination modes; fan may run but no heat.
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 first: Unplug the microwave and allow it to cool completely before inspection.
Steps to address E12:
- 1. Confirm mode-specific issue: Test normal microwave mode. If microwave heating works but E12 appears only in convection or combo modes, the convection system is at fault.
- 2. Listen for convection fan: In convection preheat, you should hear a strong fan noise. If the fan runs but no heat is produced, the heater or its sensor may be open.
- 3. Check for airflow blockage: Ensure the rear convection air outlets inside the cavity are not blocked by foil or large dishes.
- 4. Reset: Unplug for 10 minutes, then retry a convection preheat. If E12 reappears quickly, internal components require testing.
Technician-level repair: Remove the outer cabinet, test the convection heater element for continuity, check the convection thermostat/thermistor, and inspect wiring. Replace any failed parts with Toshiba-compatible components.
Repair Difficulty
Required Part
We may earn a commission from links on this page.