INTAKE OXYGEN SENSOR RATIONALITY DIAGNOSTICS

• Main Authors: STACK ROBERT, WU ZHIJIAN J, GUO YICHAO
• Format: Patent
• Language: English
• Published: 19.05.2016
• Subjects: BLASTING; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MECHANICAL ENGINEERING; SUPPLYING COMBUSTION ENGINES IN GENERAL, WITH COMBUSTIBLEMIXTURES OR CONSTITUENTS THEREOF; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; WEAPONS

Rationality diagnostic techniques for an intake oxygen sensor are utilized to detect sensor malfunction. A non-intrusive diagnostic technique includes passively detecting when an exhaust gas recirculation (EGR) valve position crosses low/high position thresholds, whereas an intrusive diagnostic technique includes actively commanding the EGR valve to predetermined low/high positions. During a period after the EGR valve position reaches/crosses at least one of the low/high positions/position thresholds, respectively, maximum and minimum intake oxygen concentration is monitored. When the EGR valve position has crossed both the low/high positions/position thresholds and a difference between the maximum and minimum oxygen concentrations is less than a respective difference threshold, a malfunction of the intake oxygen sensor is detected. A malfunction indicator lamp (MIL) could be set to indicate the malfunction. The intrusive technique is additionally or alternatively implemented, such as part of a verification or backup to the non-intrusive technique.