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:
Jun. 13, 2017
Filed:
Jul. 06, 2015
GM Global Technology Operations Llc, Detroit, MI (US);
GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US);
Abstract
An electronic control module for operating an internal combustion engine is disclosed. The electronic control module is configured to monitor a first air-fuel equivalence ratio of engine exhaust gases upstream of a NOx trap, and to activate a diagnostic routine for the NOx trap when the first air-fuel equivalence ratio is smaller than one. The diagnostic routine enables the electronic control module to monitor a second air-fuel equivalence ratio of engine exhaust gases downstream of the NOx trap, to use the first and second air-fuel equivalence ratios to calculate an index that is representative of the conversion efficiency of the NOx trap, and to identify a failure of the NOx trap when the efficiency index is lower than a predetermined threshold value.