Method and apparatus for detecting a defective pressure switch

• Main Authors: Ehmer, Norbert, Proger, Thomas, Zenzen, Markus
• Format: Patent
• Language: English
• Published: 05.11.2002

The present invention relates to a method of detecting a defective condition on a pressure switch assembly and to an arrangement for detecting a defective condition of a pressure switch assembly. The invention provides a method of detecting a defective condition on a pressure switch arrangement which at least assumes a defective condition on the said pressure switch assembly whenever a signal arrives at an input of an electronic computing unit which cannot be associated either to the opened or to the closed condition of the pressure switch. Moreover, a defective condition on the pressure switch arrangement mounted in the brake system of a vehicle is assumed, once the pressure switch signal refers to an actuated brake although the vehicle is significantly accelerated. Conversely, a defective condition is also assumed if the vehicle significantly decelerates although the pressure switch signal refers to a lack of brake pressure. Also, an appropriate pressure switch arrangement is provided which, with the pressure switch closed, generates a rectangular signal and, with the pressure switch opened, generates a high level on the input II of an electronic computing unit. With an incoming low level, an error on the pressure switch arrangement is assumed.