Bosch

All Bosch Microwave Error Codes

Every known Bosch microwave error code with plain-English explanations, difficulty ratings, and step-by-step DIY fix guides.

10 error codes

E01

The magnetron has overheated and the protection circuit has activated.

Advanced Fix 30–60 minutes
E02

The oven cavity temperature sensor has failed.

Advanced Fix 30–60 minutes
E04

The door switch circuit is not functioning correctly.

Advanced Fix 30–60 minutes
E08

The inverter board that controls microwave power has failed.

Professional Required Professional service required
E3

There is a problem with the door opening or closing mechanism.

Moderate 10–20 minutes
E11

The humidity sensor is malfunctioning or sending incorrect readings.

Easy Fix 5–15 minutes
Er4

Dangerously high temperatures detected inside the microwave cavity.

Professional Varies
Er11

One or more buttons on the control panel are dirty or mechanically jammed.

Easy Fix 5–10 minutes
Er18

A general technical fault has been detected in the microwave's electronics.

Professional Varies
E723

The microwave detects the door is not securely closed.

Easy Fix 5–10 minutes