Gaggenau Oven Error Code E104

E104 indicates a short-circuit fault in the PT1000 cooking compartment temperature sensor 1. The control board detected an abnormally low resistance from this sensor, which signals a short in the sensor element or its wiring. In response, the oven shuts off all heaters and runs the cooling fan at maximum speed as a safety precaution. The oven will not heat again until the sensor circuit is repaired.

No, the oven is not safe or functional for cooking while E104 is active. The control board has deliberately shut off all heating elements because the temperature sensor providing feedback to the control system is reporting a short-circuit condition. Without reliable temperature monitoring, the oven cannot regulate heat safely. Do not attempt to bypass the error and use the oven until the fault is diagnosed and corrected.

Repair costs depend on whether the problem is simply a loose connector or requires a new PT1000 sensor. If only the connector at plug X20 needs reseating or cleaning, the cost may be limited to a service call fee, typically in the range of $80 to $150. If the PT1000 sensor must be replaced, parts and labor combined can range from $150 to $400 or more depending on your location and the technician's rates. Gaggenau is a premium appliance brand, so sourcing the correct sensor may affect parts pricing.

A knowledgeable DIYer can start by inspecting and reseating the plug-in connection at plug X20 and checking the sensor cable for visible damage. If you have a multimeter, you can measure the PT1000 sensor resistance, which should read close to 1000 ohms at room temperature. If the connection check does not resolve the fault and the sensor reads near zero ohms, the sensor will need to be replaced, which requires disassembly of the oven cavity. For any work involving internal wiring or component replacement, it is advisable to consult a qualified appliance technician.

Resetting the oven by cutting power at the circuit breaker or unplugging it may temporarily clear the displayed code, but the fault will return as soon as the control board re-checks the sensor circuit. E104 is caused by a hardware fault in the PT1000 sensor or its wiring, not a software or communication glitch. A permanent fix requires inspecting plug X20, testing the sensor resistance, and repairing or replacing the faulty component.