Miele Oven Error Code F198

F198 indicates an open circuit in the cooling-air Pt1000 temperature sensor designated R30-34. The oven's control system monitors this sensor to track airflow temperatures protecting internal components, and an open circuit means the electrical path through the sensor is completely broken. The oven generates this fault to alert a technician that the sensor or its wiring requires inspection and likely replacement.

Operating the oven with an active F198 fault is not advisable. The cooling-air sensor monitors temperatures that protect internal electronics and structural components from heat damage. Without a valid sensor reading, the oven cannot confirm that cooling is functioning properly, which creates a risk of component damage or premature failure. It is best to stop using the oven and have it serviced.

Repair costs vary depending on whether the fault is a failed sensor, a wiring issue, or a connector problem. Parts costs for a replacement Pt1000 sensor typically fall in the range of $30 to $100 depending on availability and sourcing. Adding professional labor, total repair costs commonly range from $150 to $350, though this can vary based on your location and the technician's diagnostic findings.

A power reset may temporarily clear the fault display, but F198 will return as soon as the control system polls the R30-34 sensor again and finds the open circuit still present. The underlying hardware fault must be corrected before the error will stay resolved. Resetting without repair is not a recommended approach.

The primary repair step is replacing the R30-34 cooling-air temperature sensor, as outlined in Section 030-4.8 of the oven's service documentation. Before replacing the sensor, a technician should check the harness wiring and connectors for breaks, corrosion, or loose terminals, since a wiring fault can produce the same open circuit condition. If the wiring checks out, replacing the R30-34 sensor is the appropriate next step.