Method for monitoring the functionality of a temperature sensor

US7857508B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Dirk Foerstner · Stuttgart, DE
• Andreas Eckert · Ditzingen, DE
• Siegfried Goetz · Crailsheim, DE
• Joerg Neumann · Nuremberg, DE

Key dates

• Filing date: Oct 24, 2005
• Grant date: Dec 28, 2010
• Expiry date: May 20, 2027

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/40
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

In a method for monitoring the functionality of a temperature sensor that can deliver an electrical signal as a function of the measured temperature and is disposed, in particular, in the cooling water circuit of an internal combustion engine, the persistence of the temperature sensor in the high signal range is made possible by a method encompassing the following steps: Characterizing the sensor as possibly faulty if the sensor indicates, upon engine shutdown, at least a maximum value of the cooling fluid temperature; determining a first gradient of the cooling fluid temperature, measured by the possibly faulty sensor, up to a first point in time after engine shutdown, and characterizing the sensor as fault-free if the gradient exceeds a minimum value; determining a second gradient of the cooling fluid temperature, measured by the possibly faulty sensor, between the point in time and a point in time after engine shutdown, and characterizing the sensor as fault-free if the second gradient exceeds a minimum value; determining the cooling fluid temperature measured by the possibly faulty sensor at a point in time after engine shutdown, and characterizing the sensor as fault-free if t…