Nitrogen oxide sensor stuck-in-range diagnostic tool
US9121323B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 2011 |
| Grant date | Sep 1, 2015 |
| Priority date | — |
| Expiry date | Jul 2, 2034 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A vehicle includes an engine, an exhaust system, an SCR device, upstream and downstream NOx sensors, and a controller. The controller is in electrical communication with the NOx sensors, and is configured for detecting a stuck-in-range fault condition of the downstream NOx sensor during a low exhaust flow condition. The controller detects the condition, receives the upstream and downstream NOx levels from the respective upstream and downstream NOx sensors, and compares these levels to a zero or near-zero threshold when the low exhaust flow condition is active. The controller is also configured for executing a first control action when the upstream NOx level is below the threshold and the downstream NOx level exceeds the threshold, and executing a second control action when neither of the levels exceeds the threshold. A method is also disclosed for diagnosing the stuck-in-range condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.