Method and device for error detection and diagnosis in a knock sensor

US6727812B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Juergen Sauler · Stuttgart, DE
• Oskar Torno · Schwieberdingen, DE
• Axel Heinstein · Welzheim, DE
• Carsten Kluth · Stuttgart, DE
• Werner Haeming · Neudenau, DE

Key dates

• Filing date: Jun 18, 2002
• Grant date: Apr 27, 2004
• Expiry date: Jun 18, 2022

Classification

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

Abstract

A method and a device for fault detection or diagnosis may be used on a multi-cylinder internal combustion engine with a knock sensor. For diagnostic purposes an instantaneous reference value formed from the sensor signal may be compared with predefinable upper or lower reference threshold levels. If the instantaneous reference value exceeds or falls below the thresholds to a predefinable extent, a malfunction is detected. The reference levels correspond, for example, to the background noise present in knock-free operation. The fault detection or diagnosis may be performed only for the cylinder which emits the loudest noise or from which the loudest noise is recorded.