Abstract: An exhaust gas sensor assembly for a vehicle includes a sampling tube having a proximal end connectable to a housing and a distal end configured to be suspended with a cavity of the housing. The tube defines a hollow center, an inlet, an outlet, and an exhaust gas flow path extending from the inlet, through the hollow center, and to the outlet. An exhaust gas sensor is disposed in the hollow center at the proximal end and includes a sensing element disposed in the exhaust gas flow path. a flow guide is disposed in the hollow center between the inlet and the sensing element and is configured to redirect the flow path through a passageway defined between the tube and the flow guide.

Abstract: Methods and systems are provided for an oxygen sensor heater. In one example, a method may include applying a less than maximum duty cycle of voltage to the oxygen sensor heater during an engine cold start (e.g., when a temperature of the oxygen sensor is less than its light-off temperature) and adjusting the applied duty cycle of voltage to maintain a constant amount of power. In this way, the oxygen sensor may be heated at a constant rate even as a resistance of the oxygen sensor heater increases, decreasing an amount of time before the oxygen sensor reaches its light-off temperature.

Abstract: Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on output from an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. The sensor uses a combination of raw echo times and processed fluid level data to estimate the fluid level accurately and reliably.

Abstract: Methods and systems are provided for an oxygen sensor heater. In one example, a method may include applying a less than maximum duty cycle of voltage to the oxygen sensor heater during an engine cold start (e.g., when a temperature of the oxygen sensor is less than its light-off temperature) and adjusting the applied duty cycle of voltage to maintain a constant amount of power. In this way, the oxygen sensor may be heated at a constant rate even as a resistance of the oxygen sensor heater increases, decreasing an amount of time before the oxygen sensor reaches its light-off temperature.

Abstract: Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations. An ultrasonic sensor positioned in a recess at the bottom of the vertical standpipe transmits signals intermittently, receives their echoes upon reflection from the coolant surface, and estimates the fluid level in the standpipe based on echo times.

Abstract: An improved two-wire hall-effect speed sensor circuit includes two separate voltage regulation circuits. The voltage regulator circuits, hall plates, signal processing circuits, and output stage are implemented on an application specific integrated circuit (ASIC). In addition to a supply terminal and a return terminal, the ASIC includes an intermediate terminal. Both voltage regulation circuits may be aided by capacitors, one between the supply terminal and the return terminal, the other between the intermediate terminal and the return terminal. The speed sensor circuit is suitable for use with non-twisted wires, enabling use of a common supply wire for multiple sensors, thus reducing the number of terminals required on the controller and on connectors.

Abstract: Various systems and methods are described for a particulate matter sensor coupled to an exhaust system of an engine. One example method comprises, during a measurement mode, generating a particulate flow rate based on the sensor and adjusting one or more engine operating parameters based on the flow rate. The method further includes, during a reduced contamination mode, heating the sensor to repel particulate from the sensor, and not adjusting the one or more operating parameters based on the sensor.

Abstract: An improved two-wire hall-effect speed sensor circuit includes two separate voltage regulation circuits. The voltage regulator circuits, hall plates, signal processing circuits, and output stage are implemented on an application specific integrated circuit (ASIC). In addition to a supply terminal and a return terminal, the ASIC includes an intermediate terminal. Both voltage regulation circuits may be aided by capacitors, one between the supply terminal and the return terminal, the other between the intermediate terminal and the return terminal. The speed sensor circuit is suitable for use with non-twisted wires, enabling use of a common supply wire for multiple sensors, thus reducing the number of terminals required on the controller and on connectors.

Abstract: Methods and systems are provided for detecting leaks in a diesel particulate filter (DPF). In one example, a faster leak detection routine may be performed during a single drive cycle to detect large leaks in the DPF. However, if there are no large leaks in the DPF, a slower leak detection may be performed over a plurality of drive cycles, to detected smaller leaks in the DPF.

Abstract: Methods and systems are provided for detecting leaks in a diesel particulate filter (DPF). In one example, a faster leak detection routine may be performed during a single drive cycle to detect large leaks in the DPF. However, if there are no large leaks in the DPF, a slower leak detection may be performed over a plurality of drive cycles, to detected smaller leaks in the DPF.

Abstract: Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on output from an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. Sensor power usage is optimized based on the ratio of first order and higher order harmonic echo times in the raw data set generated by the sensor.

Abstract: Systems and methods for improving hybrid vehicle torque control are presented. The system and methods included may estimate driveline torque via springs of a dual mass flywheel. The estimated driveline torque may provide feedback for adjusting operation of a driveline disconnect clutch and/or engine torque.

Abstract: Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations. An ultrasonic sensor positioned in a recess at the bottom of the vertical standpipe transmits signals intermittently, receives their echoes upon reflection from the coolant surface, and estimates the fluid level in the standpipe based on echo times.

Abstract: Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on output from an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. Sensor power usage is optimized based on the ratio of first order and higher order harmonic echo times in the raw data set generated by the sensor.

Abstract: Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on output from an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. The sensor uses a combination of raw echo times and processed fluid level data to estimate the fluid level accurately and reliably.

Abstract: Systems and methods for improving hybrid vehicle torque control are presented. The system and methods included may estimate driveline torque via springs of a dual mass flywheel. The estimated driveline torque may provide feedback for adjusting operation of a driveline disconnect clutch and/or engine torque.

Abstract: A method and system provides a Neutral Hold mode in a vehicle having a shift-by-wire transmission with a return to park feature. The Neutral Hold mode is entered upon detecting when the transmission control mechanism has been used a first time to select Neutral when a driver's door is open or has been used a second time to select Neutral. When in Neutral Hold mode, the transmission will stay in Neutral and not shift to Park upon detecting that a driver has exited the vehicle.

Abstract: Various systems and methods are described for a particulate matter sensor coupled to an exhaust system of an engine. One example method comprises, during a measurement mode, generating a particulate flow rate based on the sensor and adjusting one or more engine operating parameters based on the flow rate. The method further includes, during a reduced contamination mode, heating the sensor to repel particulate from the sensor, and not adjusting the one or more operating parameters based on the sensor.

Abstract: A method and system provides a Neutral Tow mode in a vehicle with a shift-by-wire transmission by displaying a Neutral Tow mode option when the transmission control mechanism has been used to select Park, an ignition switch is on, and an engine is off or an information button has been pushed and entering a Neutral Tow mode upon detecting a triggering event. The Neutral Tow mode is canceled upon detecting a certain sequence of events, such as turning on the ignition switch, depressing and holding a brake pedal, and selecting Park. When in Neutral Tow mode the transmission will stay in Neutral, without automatically shifting to Park or using battery power, thereby enabling the vehicle to be towed long distances without draining battery power.

Abstract: A method and system provides a Neutral Tow mode in a vehicle with a shift-by-wire transmission by displaying a Neutral Tow mode option when the transmission control mechanism has been used to select Park, an ignition switch is on, and an engine is off or an information button has been pushed and entering a Neutral Tow mode upon detecting a triggering event. The Neutral Tow mode is canceled upon detecting a certain sequence of events, such as turning on the ignition switch, depressing and holding a brake pedal, and selecting Park. When in Neutral Tow mode the transmission will stay in Neutral, without automatically shifting to Park or using battery power, thereby enabling the vehicle to be towed long distances without draining battery power.