Gaggenau Range Error Code F15

The F15 error code on a Gaggenau range indicates a fault in the NTC (Negative Temperature Coefficient) sensor circuit, specifically a short circuit condition. NTC sensors are thermistors that change resistance in response to temperature, and the power electronics module uses these resistance readings to monitor and regulate cooking temperatures. When a short circuit occurs in this circuit, the sensor signal collapses to an abnormal low-resistance or zero-resistance state, which the control system interprets as a critical fault and halts operation to prevent damage or unsafe conditions.

A short circuit in the NTC sensor circuit can originate at the sensor itself, in the wiring harness connecting the sensor to the electronics board, or within the power electronics module. A failed sensor with internally shorted leads will present near-zero resistance regardless of temperature. Similarly, pinched, chafed, or heat-damaged wiring can allow two conductors to contact each other, creating a short at the harness level. In some cases, the fault lies within the power electronics board itself, where a component on the sensor input circuit has failed and is generating the false short circuit reading internally.

Because the first recommended diagnostic step is to replace the power electronics, the fault is considered likely to originate within or be unresolvable without replacing that board. This approach reflects that the power electronics module both powers and reads the NTC sensor circuit, making it difficult to fully isolate a sensor fault from an internal board fault without substitution. Technicians should also inspect the sensor and its wiring for visible damage before committing to a board replacement.