METHOD FOR OPERATING A PROBE

摘要

The invention relates to a method for operating a probe having a pumped reference cell. A first time (T1) is determined, at which a pulse-width-modulated pump current applied to the reference cell is switched on. In accordance with the first time (T1), at least one first voltage characteristic value (Vref1) is determined within a specified first time frame (F1), the at least one first voltage characteristic value being representative of a voltage applied to the reference cell. The pulse-width-modulated pump current applied to the reference cell is switched off at a second time (T2). A third time (T3) is determined, at which a pulse-width-modulated pump current applied to the reference cell is switched off. In accordance with the third time (T3), at least one second voltage characteristic value (Vref2) is determined within a specified second time frame (F2), the at least one second voltage characteristic value being representative of the voltage applied to the reference cell. In accordance with the at least one first voltage characteristic value (Vref1) and the at least one second voltage characteristic value (Vref2), a diagnostic characteristic value (D) is determined, which is representative of an error in the determination of the nitrogen oxide concentration.