The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 16, 2004
Filed:
Nov. 29, 2001
Masaki Nakamichi, Tokyo, JP;
Ryoichi Hanazaki, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An O -sensor fault diagnosis apparatus and method therefor, which are capable of detecting wire breaking of an O -sensor with reliability and successively performing fault diagnosis with minimal effect on an exhaust gas. An O -sensor detects concentration of oxygen contained in an exhaust gas of an engine An ECU controls a quantity of fuel supplied to the engine through feedback control according to an output signal of the O -sensor. A fault diagnosis portion changes an input resistance value of an input circuit that is connected to the O -sensor and constitutes the ECU each time a control condition for determining that the O -sensor is in an inactive state is satisfied, determines that wire breaking occurs in the O -sensor only if the output voltage of the O -sensor exceeds a predetermined voltage, and activates an informing portion to send a notice showing that there is a fault in the O -sensor