Method for monitoring the function of a gas sensor and/or for regenerating the same

A method for monitoring the function and/or regeneration of a gas probe, the gas probe including:

• a heatable probe ceramic which detects gas molecules, a first pump electrode arranged in a chamber, and a second pump electrode arranged in the exhaust gas of the engine, the method comprising the steps of:
• a) providing a pump voltage source and applying a pump voltage across the first and second pump electrodes so that an oxygen partial pressure is adjusted in the interior of said chamber by electrochemically pumping away the oxygen molecules;
• b) applying a first pump voltage and measuring a first pump current;
• c) applying a second pump voltage, which is higher or lower compared to the first pump voltage, and measuring a second pump current;
• d) forming the difference (ΔI) of the first and second pump currents;
• e) if the difference (ΔI) exceeds a pregiven value, applying a previously determined saturation pump voltage and comparing a resulting pump current to a previously stored minimum pump current;
• f) forming the difference of the minimum pump current and of the resulting pump current (ΔI plus);
• and
• g) if the difference (ΔI plus) of the minimum pump current and of the resulting pump current exceeds a pregiven amount, applying a regeneration voltage, wherein the is generated by a further pump source, which regeneration voltage is greater than the saturation voltage.