Patent application number | Description | Published |
20110047971 | DOSING CONTROL SYSTEMS AND METHODS - A dosing control system for a vehicle includes a pump control module and an enabling/disabling module. The pump control module controls a pump that provides dosing agent to a dosing agent injector located upstream of a selective catalytic reduction (SCR) catalyst in an exhaust system. The enabling/disabling module disables the pump for a predetermined melting period after engine startup when the dosing agent is frozen and selectively activates the pump during the predetermined melting period to cool the dosing agent injector when a tip temperature of the dosing agent injector is greater than a predetermined temperature. | 03-03-2011 |
20120000187 | PARTICULATE FILTER REGENERATION INTERRUPTION SYSTEMS AND METHODS - A regeneration control system for a vehicle includes a regeneration control module and a regeneration interrupt module. The regeneration control module selectively provides fuel to an oxidation catalyst for a regeneration event of a particulate filter that occurs during a predetermined melting period for frozen dosing agent. The regeneration interrupt module selectively interrupts the regeneration event and disables the provision of fuel to the oxidation catalyst before the regeneration event is complete when a temperature of a dosing agent injector that is located between the oxidation catalyst and the particulate filter is greater than a predetermined temperature. | 01-05-2012 |
20120260625 | NITROGEN OXIDE SENSOR STUCK-IN-RANGE DIAGNOSTIC TOOL - 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. | 10-18-2012 |
20130014575 | EXHAUST DIAGNOSTIC SYSTEM AND METHOD WITH SCR NH3 DEPLETION CLEANSING MODE FOR INITIAL STEP IN THE DEF QUALITY SERVICE HEALING TEST - An exhaust diagnostic system comprises a selective catalyst reduction (SCR) component testing module, an exhaust stream temperature management module, and a test enabling module. The component testing module executes an SCR component efficiency test. The exhaust stream temperature management module adjusts a temperature of the SCR component to a predetermined temperature range. The test enabling module executes a process for depleting a reductant load and subsequently initiates an SCR component efficiency test while the temperature of the SCR catalyst is within the predetermined temperature range. | 01-17-2013 |
20130276428 | EXHAUST DIAGNOSTIC CONTROL SYSTEM AND METHOD WITH NH3 DEPLETION CLEANSING - An exhaust diagnostic control system comprises a test enabling module, an exhaust gas temperature management module, and an exhaust diagnostic control system. The test enabling module is configured for executing a process for depleting a reductant load and subsequently establishing a known concentration of reductant on an after-treatment component following an occurrence of one or more trigger events. The exhaust gas temperature management module is configured for selectively adjusting a temperature of the after-treatment component to a predetermined temperature range using intrusive exhaust gas temperature management. The component management module is configured for executing a NOx reduction efficiency test following completion of the process for depleting a reductant load and subsequently establishing a known concentration of reductant on the after-treatment component. The NOx reduction efficiency test comprises determining a NOx reduction efficiency associated with the after-treatment component. | 10-24-2013 |
20130291517 | EXHAUST DIAGNOSTIC CONTROL SYSTEM AND METHOD WITH SELECTIVE DISABLEMENT OF NOX REDUCTION EFFICIENCY DIAGNOSTIC - An exhaust diagnostic control system comprises a test enabling module, an exhaust gas temperature management module in communication with the test enabling module, and a component management module configured for executing a test for determining a reduction efficiency associated with the after-treatment component. The test enabling module is configured for assessing a reliability of an estimated level of reductant load on an after-treatment component, and, based on the reliability, selectively facilitating disablement of a subsequent test for determining an efficiency of NOx reduction in the after-treatment component. The exhaust gas temperature management module is configured for selectively adjusting a temperature of the after-treatment component to a predetermined temperature range using intrusive exhaust gas temperature management. The test for determining reduction efficiency comprises determining a NOx reduction efficiency of the after-treatment component. | 11-07-2013 |
20130338900 | NOX SENSOR PLAUSIBILITY MONITOR - A vehicle includes an engine, an exhaust system, and a controller. The exhaust system includes a selective catalytic reduction (SCR) device, and a rear nitrogen oxide (NOx) sensor. The controller, which is in communication with the NOx sensor, includes a processor and tangible, non-transitory memory. A plurality of data maps and a plurality of binary maps are recorded in memory. Each data map is indexed by a different pair of exhaust system performance values. Each cell of each data map is populated by estimated downstream NOx levels. The binary maps are indexed by one of the pairs of exhaust system performance values. Each cell of each binary map is populated by a binary value, i.e., a 0 or 1. The controller uses the data maps and the binary maps to execute a control action with respect to the exhaust system, such as verifying plausibility of the rear NOx sensor. | 12-19-2013 |
20140144220 | DIAGNOSTIC OPERATION STRATEGY FOR DIESEL OXIDATION CATALYST AGING LEVEL DETERMINATION USING NOX SENSOR NO2 INTERFERENCE - A method of determining aging of a diesel oxidation catalyst (DOC) in an engine exhaust system includes receiving a first sensor signal from a first nitrogen oxides (NOx) sensor positioned in exhaust flow upstream of the DOC. The first sensor signal is indicative of an amount of NOx in the exhaust flow upstream of the DOC. The method further includes receiving a second sensor signal from a second NOx sensor positioned in the exhaust flow downstream of the DOC. The second sensor signal is indicative of an amount of NOx downstream of the DOC. A difference between the first sensor signal and the second sensor signal is calculated by a controller. A DOC aging level based on a predetermined correlation between the difference and DOC aging can then be determined by the controller if at least one predetermined operating condition is satisfied. | 05-29-2014 |