Bosch Microwave Error Code Er18 — Technical Fault
What this means
Error Er18 is a general technical fault code indicating an issue with the microwave's internal electronics. This could be caused by a power surge, a failing component on the control board, or a communication error between internal modules.
Step-by-step fix
3 stepsPower cycle
Unplug the microwave for 10 minutes and plug it back in.
Power surges are a common trigger for this error.
Test basic operation
Try running a 30-second cycle to see if the microwave heats. If it does, the error may have been temporary.
Contact Bosch service
If the error returns, the internal electronics need professional diagnosis.
Have your model number ready when calling.
When to call a professional
If power cycling does not clear the error, professional service is required. Do not attempt to open the microwave enclosure.
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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