Patent ID: 7654077

Claim:
A method for controlling operation of an exhaust-gas sensor disposed in an exhaust duct of a motor vehicle and equipped with one of (a) an internal and (b) an external sensor heating device, the motor vehicle including a combustion engine and an automatic switchoff configured to cause an automatic switching off of the combustion engine when at least one stop condition is present, comprising: following an automatic switching off of the combustion engine by the automatic switchoff, determining a first future instant at which an exhaust-gas temperature in the exhaust duct will drop below a condensation temperature below which condensate precipitation from the exhaust gas may occur; determining a second instant at which a heat output of the sensor heating device must be one of (a) interrupted and (b) reduced so that a sensor temperature of the exhaust-gas sensor will have dropped to a maximally allowed sensor temperature no later than the first future instant; and one of (a) interrupting and (b) reducing heat output of the sensor heating device when the second instant is attained.