Abstract: Methods and apparatus are disclosed for hue adjustment of a vehicle display based on ambient light. An example vehicle includes a display, an ambient light sensor to monitor ambient light of the vehicle, and a master lighting controller. The example master light controller is to determine a target hue for the display based on the ambient light, compare the target hue to a current hue of the display, and, in response to the target hue being different than the current hue, adjust the current hue to the target hue.

Abstract: Methods and systems are provided for conducting measurements of relative humidity via the use of either an ultrasonic sensor positioned on the vehicle, or via another sensor. In one example, responsive to a request for a relative humidity measurement and an indication of fueled engine operation, the ultrasonic sensor may be utilized, whereas responsive to an indication of non-fueled engine operation, another sensor may be utilized. In this way, robust measurement of relative humidity with desired accuracy may be actively determined, rather than opportunistically, and such measurements of relative humidity may be utilized to adjust vehicle operating parameters, which may improve overall vehicle operation.

Abstract: Methods and systems are provided for conducting measurements of relative humidity via the use of an ultrasonic sensor. In one example, the ultrasonic sensor for conducting the relative humidity measurement is selected from a plurality of ultrasonic sensors positioned at various locations on the vehicle, and where the selecting is accomplished in some examples via the use of one or more onboard cameras configured to identify suitable objects that are stationary with respect to the vehicle. In this way, robustness and accuracy of relative humidity measurements may be improved, lifetime of individual ultrasonic sensors may be extended, and vehicle operating conditions that depend on accurate relative humidity measurements may be improved.

Abstract: Methods and systems are provided for leveraging the pressure dependency of an oxygen sensor for estimating an engine ambient pressure. An intake or exhaust oxygen sensor is used for ambient pressure estimation by applying a reference voltage to the sensor while the engine is being pulled-down in a hybrid vehicle, and correcting an output of the sensor for dilution effects due to ambient humidity. The estimated ambient pressure is used to correct or confirm pressure estimated by other sources, such as other pressure sensors or a pressure model, as well as to tune the performance of the engine.

Abstract: A method for an engine may comprise, responsive to a first condition comprising a reference voltage of a first exhaust oxygen sensor operating in variable voltage mode increasing above a threshold voltage, determining a change in an output of the first exhaust oxygen sensor corresponding to the increase in the reference voltage, correcting the output of the first oxygen sensor based on the output change, and adjusting engine operation based on the corrected output. In this way, the accuracy of air-fuel estimates based on the exhaust gas sensor can be preserved, and closed loop fuel control of the engine can be maintained even when the exhaust oxygen sensor is operating VVS mode, thereby reducing engine emissions, increasing fuel economy, and increasing vehicle drivability.

Abstract: Methods and systems are provided for estimating an amount of exhaust gas recirculation (EGR) from an exhaust passage into an intake passage of an engine system by operating an exhaust oxygen sensor in a variable voltage (VVs) mode. In one example, a method includes during operation of an exhaust oxygen sensor in the VVs mode where a reference voltage of the exhaust oxygen sensor is adjusted from a lower, first voltage to a higher, second voltage, adjusting engine operation based on the EGR amount estimated based on an output of the exhaust oxygen sensor and a learned correction factor based on the second voltage. In this way, the exhaust oxygen sensor may be used to correct for variations arising due to changing fuel composition and ambient humidity and further used to estimate the amount of EGR being recirculated in the system, thereby enhancing engine fueling and EGR control.

Abstract: A communication system for a vehicle includes an accelerometer, and a controller electrically coupled to the accelerometer and configured to respond to a signal indicative of an accident of the vehicle. The controller's response to the signal includes activating an emergency mode, requesting biometric data of occupants of the vehicle, and transmitting data identifying the vehicle, a location of the vehicle and a time of activation, and biometric data.

Abstract: Methods and systems are provided for reducing blackening of an oxygen sensor due to voltage excursions into an over-potential region. Before transitioning the sensor from a lower voltage to an upper voltage during variable voltage operation, an operating temperature of the sensor is reduced via adjustments to a sensor heater setting. The reduction in temperature increases the range of temperatures available to the sensor before the over-potential region is entered.

Abstract: Various methods for operating an oxygen sensor are provided. In one example, a method of operating an oxygen sensor comprises applying power to a heater of the oxygen sensor, and indicating whether water is in contact with the oxygen sensor based on a time rate of change of a temperature of the oxygen sensor.

Abstract: Methods and systems are provided for detecting a temperature of an engine fuel rail at a plurality of locations along the engine fuel rail. In one example, a method may include detecting temperatures along the engine fuel rail with a plurality of metal film thermocouples adhered to the engine fuel rail and arranged proximate to engine fuel injectors, and adjusting fuel injector operation and/or fuel rail pressure in response to the detected fuel rail temperatures.

Abstract: Methods and systems are provided for reducing blackening of an oxygen sensor due to voltage excursions into an over-potential region. Before transitioning the sensor from a lower voltage to an upper voltage during variable voltage operation, an operating temperature of the sensor is reduced via adjustments to a sensor heater setting. The reduction in temperature increases the range of temperatures available to the sensor before the over-potential region is entered.

Abstract: Methods and systems are provided for detecting a temperature of an engine fuel rail at a plurality of locations along the engine fuel rail. In one example, a method may include detecting temperatures along the engine fuel rail with a plurality of metal film thermocouples adhered to the engine fuel rail and arranged proximate to engine fuel injectors, and adjusting fuel injector operation and/or fuel rail pressure in response to the detected fuel rail temperatures.

Abstract: Methods and systems are provided for accurately determining the composition of a knock control fluid using sensors already present in the engine system. An intake oxygen sensor is used to estimate the water and the alcohol content of a knock control fluid that is direct injected into an engine cylinder responsive to an indication of abnormal combustion. A change in the pumping current of the oxygen sensor due to the water content of the knock control fluid is distinguished from a change in the pumping current of the oxygen sensor due to the alcohol content of the knock control fluid, while compensating for interfering effects of intake air diluents on the change in pumping current.

Abstract: Methods and systems are provided for adjusting heater power of an oxygen sensor. In one example, a method for an engine includes adjusting heater power of a heating element of the oxygen sensor when the heater power increases by a threshold amount. The method includes subsequently increasing heater power back to a baseline power level responsive to a temperature of the heating element.

Abstract: Methods and systems are provided for accurately estimating intake aircharge based on the output of an intake oxygen sensor while flowing EGR, purge, or PCV hydrocarbons to the engine. The unadjusted aircharge estimate is used for engine fuel control while the hydrocarbon adjusted aircharge estimate is used for engine torque control. A controller is configured to sample the oxygen sensor at even increments in a time domain, stamp the sampled data in a crank angle domain, store the sampled data in a buffer, and then select one or more data samples corresponding to a last firing period from the buffer for estimating the intake aircharge.

Abstract: A vehicle includes a communication system. The communication system includes at least one controller and may include an RF transceiver. The controller is configured to receive a distress signal including emergency information and a relay count. The controller is configured to respond, when the relay count is less than a predetermined number and a location of the vehicle is greater than a predetermined distance away from a transmission location and an origination location of the distress signal, by causing the emergency information to be transmitted with an incremented relay count. The controller may be further configured to respond to the location of the vehicle being between the origination location and at least one transmission location by inhibiting the transmitting of the emergency information.

Abstract: Methods and systems are provided for adjusting heater power of an oxygen sensor. In one example, a method for an engine includes adjusting heater power of a heating element of the oxygen sensor when the heater power increases by a threshold amount. The method includes subsequently increasing heater power back to a baseline power level responsive to a temperature of the heating element.

Abstract: A method for an engine may comprise, responsive to a first condition comprising a reference voltage of a first exhaust oxygen sensor operating in variable voltage mode increasing above a threshold voltage, determining a change in an output of the first exhaust oxygen sensor corresponding to the increase in the reference voltage, correcting the output of the first oxygen sensor based on the output change, and adjusting engine operation based on the corrected output. In this way, the accuracy of air-fuel estimates based on the exhaust gas sensor can be preserved, and closed loop fuel control of the engine can be maintained even when the exhaust oxygen sensor is operating VVS mode, thereby reducing engine emissions, increasing fuel economy, and increasing vehicle drivability.

Abstract: Methods and systems are provided for leveraging the pressure dependency of an oxygen sensor for estimating an engine ambient pressure. An intake or exhaust oxygen sensor is used for ambient pressure estimation by applying a reference voltage to the sensor while the engine is being pulled-down in a hybrid vehicle, and correcting an output of the sensor for dilution effects due to ambient humidity. The estimated ambient pressure is used to correct or confirm pressure estimated by other sources, such as other pressure sensors or a pressure model, as well as to tune the performance of the engine.

Abstract: The present description relates generally to methods and systems for detecting thermal aging and blackening in oxygen sensors. Thermal aging and blackening effects may be differentiated based on a monitored change in impedance in each of a pump cell and a Nernst cell of the oxygen sensor following application of an alternating voltage. In response to detection of thermal aging and/or blackening in the oxygen sensor corrective measures may be taken to ensure accurate oxygen estimation using the sensor.