Abstract: An apparatus is provided for diagnosing the state of health of a vehicle and for providing the operator of the vehicle with a substantially real-time indication of the efficiency of the vehicle in performing an assigned task with respect to a predetermined goal. A processor on-board the vehicle monitors sensors that provide information regarding the state of health of the vehicle and the amount of work the vehicle has done. In response to anomalies in the data from the sensors, the processor records information that describes events leading up to the occurrence of the anomaly for later analysis that can be used to diagnose the cause of the anomaly. The sensors are also used to prompt the operator of the vehicle to operate the vehicle at optimum efficiency.

Abstract: A method for responding to conditions detected in an on-board diagnostic unit of a motor vehicle and signaling degradation of a component of the motor vehicle. The method includes providing a first response if the conditions signal degradation of the component due to tampering, and providing a second response if the conditions signal degradation of the component not due to tampering.

Abstract: The present invention relates to an electric vehicle and a method for controlling an emergency thereof, wherein: a plurality of control units are comprised in such a manner that the plurality of control units monitor one another; and emergency control is performed through a control unit which will normally operate in the case of an abnormal occurrence, such that the vehicle is driven within a limited range, or the vehicle is stopped according to the abnormal occurrence, thereby ensuring driving stability and preventing accidents caused by the abnormality of the vehicle to guarantee the safety of a driver.

Abstract: An embodiment of the present disclosure provides a method, apparatus, and computer program product for testing hardware. A number of commands are identified for a testing unit. A communication layer of the testing unit is requested to send the number of commands to a controller unit for a platform. The testing unit is remote from the controller unit. The number of commands is coordinated with the controller unit. Results of the number of commands of the testing unit are received through the communication layer.

Abstract: A method of valve lift failure detection may include determining first and second intake air pressures in an engine having intake valve lifters that selectively operate intake valves in first and second lift modes. The first intake air pressure may correspond to an intake stroke of a first piston of the engine when the engine is commanded to operate in the first lift mode and the second intake air pressure may correspond to an intake stroke of a second piston of the engine when the engine is commanded to operate in the first lift mode. The method may further include determining a difference between the first and second intake air pressures and diagnosing an intake valve lifter failure when the difference exceeds a predetermined limit.

Abstract: An method for controlling a parallel hybrid drive-train of a vehicle comprising an automatic transmission and a combustion engine which is connected, via a first shifting device, to an electrical machine, which is connected, via a drive shaft, a starting clutch positioned in the transmission. To guarantee safety and high drive comfort of the vehicle during failure of the starting clutch, shifting failures of the starting clutch are monitored. If a shifting failure is recognized, predetermined contingency procedures are initiated and executed in which either continued drive of the vehicle or slowing down of the vehicle to a stop is possible. A device comprises a monitor with a sensor and parts for analyzing and recognizing shifting failures of the starting clutch. Control parts initiate and execute contingency procedures such that a continued drive operation or slowing down of the vehicle to a stop is possible.

Abstract: A driver assistance system includes a speed detector, a preceding vehicle detector having at least one video camera and at least one distance sensor for detecting the distance from a preceding vehicle, a device for determining the speed of the preceding vehicle, and an electronic control unit equipped to trigger an autonomous deceleration of the vehicle with the presence of predetermined brake trigger driving data and to terminate the autonomous deceleration with the presence of predetermined brake abortion driving data. The control unit effects: redundant detection of preceding vehicle driving data, and non-redundant detection of preceding vehicle driving data if a redundant detection is not possible. The non-redundantly detected preceding vehicle driving data is compared to preceding vehicle driving data redundantly detected within a predetermined time, and the non-redundantly detected data is used to control the autonomous deceleration if it corresponds to the redundantly detected data.

Abstract: A self-diagnostic device for an acceleration or angular-velocity sensor includes a diagnosis control unit, an integration unit, and a determination unit. The diagnosis control unit provides pseudo acceleration or angular velocity to a sensor main body for detecting acceleration or angular velocity, by applying a test signal having prescribed magnitude to the sensor main body. The integration unit integrates a sensor signal outputted from the sensor main body in response to the test signal. The determination unit determines whether or not an integration value obtained at an elapse of prescribed integration time from a time point when the integration unit starts integrating the sensor signal falls within a prescribed normal range.

Abstract: A valve ID registration system includes a sudden pressure decrease detector that detects a sudden pressure decrease in the tire and a transmission unit that transmits a valve signal. When the detector detects a sudden pressure decrease, the transmission unit transmits the valve signal, which includes sudden pressure decrease information, with more frames than normal. A sudden pressure decrease monitoring unit monitors the received valve signal for sudden pressure decrease information. After the valve signal including the sudden pressure decrease information is received with more frames than normal, when a new valve signal is received including the same valve ID as that in the valve signal including the sudden pressure decrease information and the new valve signal indicates an increase in air pressure, a registration unit determines that the valve signals were transmitted from the tire of the vehicle and registers the valve ID.

Abstract: A device, system and method for controlling speed of a vehicle are provided. The device includes a locational information module for determining location information and speed; a storage module for storing at least one geographic map including at least one route and a speed limit for the at least one route; a processing module configured to receive the location information, retrieve at least one geographic map based on the location information, determine a speed limit based on the location information and compare the speed of the device to the determined speed limit; and a display module for alerting a user if the speed of the device exceeds the determined speed limit. The system and method can be for communicating a subject vehicle's speed to a central server where it can be utilized to analyze traffic congestion patterns or notify selected companies or individuals.

Abstract: Systems and methods are provided for detecting an anomaly in a hidden portion of a first layer of a multi-layer structure. A monitoring element is provided on at least one exposed end of a fastener that extends through the multi-layer structure, and another monitoring element on an exposed portion of the first layer. With at least one of the monitoring elements, an inspection signal is introduced into the multi-layer structure including the hidden portion of the first layer. The inspection signal is then sensed with at least another one of the monitoring elements following propagation of the inspection signal through at least a portion of the multi-layer structure including the hidden portion of the first layer. Finally, an anomaly may be detected in the hidden portion of the first layer based upon the inspection signal that has been sensed.

Abstract: A vehicle driving operation support apparatus for a vehicle, includes a sensing section to sense a traveling condition of the vehicle including a surrounding condition inclusive of an obstacle around the vehicle, and a control section to calculate a risk potential for the vehicle in accordance with the traveling condition. The control section performs a support control to support the driver in accordance with the risk potential, and performs an assist control to restrain disturbance (such as vibration from a road) transmitted to the driver in accordance with the risk potential.

Abstract: A vehicle control system for an automatic transmission includes a range selector for outputting a range instruction signal representing the selected shift range and a range shifter for manually outputting a shift instruction signal, and a by-wire control part for controlling the change-over of the shift range according to the range instruction signal input from the range selector. The by-wire control part has a range control circuit, which uses the shift instruction signal input from the range shifter if the range instruction signal is abnormal while monitoring the range instruction signal input from the range selector.

Abstract: A method for monitoring a starter motor for an internal combustion engine includes calculating a first engine power during a starting event based on an electric power flow from the battery to the starter motor, calculating a second engine power during the starting event based on an engine kinetic energy, and detecting a fault associated with the starter motor as a function of the difference between the first engine power and the second engine power.

Abstract: System for processing tire pressure monitor (TPM) signals. The system include capabilities to support amplitude shift key (ASK) modulation of TPM data signals transmitted from TPMs included within one or more tires of a vehicle. The system may include a receiver and controller to process the TPM signals.

Abstract: A method for detecting the direction of travel or for detecting a change in the direction of travel of a motor vehicle which has at least two wheel speed sensor arrangements which each comprise an encoder with an incremental scale and a plurality of scale graduations and a wheel speed sensor (SEa, SEb, SEc, SEd) and are connected to an electronic control unit, wherein, when a scale graduation is sensed the wheel speed sensors each transmit a speed signal to the electronic control unit, wherein the direction of travel or a change in the direction of travel is identified at least from the order in which the speed signals occur with respect to the individual wheel speed sensor arrangements. A computer program product for carrying out all the steps of the method is also disclosed.

Abstract: A method for remotely administering a fault detected on an unmanned powered system that is controlled through a lead powered system, the method including detecting an operational fault on an unmanned powered system, communicating information about the fault to the lead powered system, through a wireless communication protocol operable with a wireless communication system, and communicating a reset message to the unmanned powered system to reset the fault detected. A system and computer software code, stored on a computer readable media and executable with a processor, are also disclosed for remotely handling a fault detected on an unmanned powered system that is controlled through a lead powered system.

Abstract: Over rotation limitation control is performed to control an engine rotation speed so that a rotation speed of a pinion gear of a planetary gear set will not exceed a limit value, when a travel mode is changed to a limp-home travel mode in response to an abnormality in an inverter for a first motor generator. With this over rotation limitation control, a difference between rotation speeds of a ring gear coupled to a wheel side and a carrier coupled to an engine side. Thus, when the limp-home travel mode is performed due to the abnormality in the inverter for the first motor generator, a secondary failure, in which the pinion gear burns out and the planetary gear set fails, is prevented.

Abstract: Methods and systems for managing maintenance of a fleet of aircraft are provided. The method includes collecting data from at least one aircraft in each of the fleets related to the operation of the aircraft, determining a range of acceptable values of performance parameters associated with the collected data and based on the collected data, analyzing the collected data having values outside the range of acceptable values, and modifying at least one of a maintenance requirement and an interval between maintenance actions to facilitate reducing the number of performance parameters values that are outside the range of acceptable values during future operation of the aircraft.

Abstract: A shift-by-wire system, connected to a manual shaft in a vehicle, includes: an electric motor having a rotary shaft which rotates the manual shaft; an angle-of-rotation sensor that detects angle position of the rotary shaft for control of the electric motor; a shaft position sensor that detects angular position of the manual shaft; and a control unit that, when the angle-of-rotation sensor functions normally, controls the electric motor according to the sensed angular position of the rotary shaft, so that the sensed angular position of the shaft comes within a predetermined range, and when the angle-of-rotation sensor does not function normally, initiates sensor-less control of the electric motor while estimating the direction of rotation of the rotation shaft, based on the sensed angular position of the shaft, and ceases sensor-less control when the sensed angular position is within the predetermined range.

Abstract: Methods and systems for controlling motor torque in a hybrid vehicle are provided. A current sensor provides a feedback current when the sensor is operating properly. A processor controls the motor torque using the feedback current if the current sensor is operating properly. The processor controls the motor torque using a slip value for the hybrid vehicle if the current sensor is not operating properly.

Abstract: Analysis of a vehicle is performed using multi-dimensional infrared image data acquired for the vehicle. A component of the vehicle can be identified within the infrared image data, and the infrared image data for the component can be analyzed to determine whether any condition(s) are present on the vehicle. One or more actions can be initiated in response to a determination that a particular condition is present. Additionally, visible image data can be used to supplement the infrared image data. Still further, infrared image data for similar components imaged concurrently with the component can be used to identify whether any condition(s) are present on the vehicle. Unlike prior art approaches in the rail industry, the analysis can be performed on rail vehicles within a classification yard.

Abstract: A computer system and method wherein each vehicle in a jurisdiction, as a result of a regular or temporary registration process when the vehicle enters a jurisdiction temporarily at a border point, has a GPS receiver and transmitter installed and transmitting to a storage which stores for each vehicle identification code the location data and time An alarm detection system detects either loss of signal or tampering. A monitoring system also detects moving vehicles in an area, and positions reported by the monitoring means are compared with information being recorded on the computer system, and if these do not correlate, an unregistered vehicle alarm is generated. The system may be limited to vehicles entering at a border point, or new vehicles with GPS receivers and wireless transmitters installed at the time of manufacture.

Abstract: A vehicle driving assist system calculates a risk potential indicative of a degree of convergence between a host vehicle and a preceding obstacle. Then, the system performs a driver notification operation that produces a driver notification stimulus based on the risk potential such as decreasing the driving force exerted against the vehicle as the risk potential increases and increasing an actuation reaction force exerted on the accelerator pedal during its operation as the risk potential increases. If a failure is detected in a reaction force generating device serving to add a reaction force to the accelerator pedal in accordance with the risk potential, then the system corrects an engine torque characteristic such that the engine torque does not increase even if the accelerator pedal is depressed to suppress an odd feeling in the vehicle performance by the driver when a failure occurs in the reaction force generating device.

Abstract: A road surface frictional coefficient estimating apparatus has a device for determining a first estimated value of a yaw moment Mnsp_estm generated at an NSP of a vehicle due to the resultant force of road surface reaction forces acting on each wheel by using, for example, a frictional coefficient estimated value that has been determined, and a device for determining a second estimated value of a yaw moment Mnsp_sens generated at the NSP from the observed value of motional state amounts defining an inertial force moment at the NSP. The increasing/decreasing manipulated variable of the frictional coefficient estimated value is sequentially determined on an error (Mnsp_sens?Mnsp_estm) such that the error is converged to zero, and the road surface frictional coefficient is updated on the basis of the increasing/decreasing manipulated variable.

Abstract: Embodiments relate to systems and methods for vehicle monitoring with processing interruption tolerance. One or more vehicle sensors can transmit one or more data streams to a primary data processing system via a data channel. A secondary data buffer can be coupled to the data channel to continuously capture the set of data streams and/or subsets thereof. During normal operation, the set of data streams are processed by the primary data processing system. After a limited-duration fault occurs in the primary data processing system, it can recover by accessing the backup data in the secondary data buffer. The lost data can be retrieved from the secondary data buffer using timestamp information to process the data in its original time context and to ensure that no already-processed data is included. The set of data streams can be downsampled or decimated in the secondary data buffer to extend storage capacity.

Abstract: In a microcomputer, a signal processing device computes a control signal, such as an accelerator position, a throttle position, based on a sensor output signal, such as an output signal of an accelerator position sensor, an output signal of a throttle position sensor. A torque control device executes a torque control operation to coincide an actual torque with a requested torque based on the control signal. Furthermore, a torque monitor device determines whether a torque increase abnormality exists based on the control signal. A signal abnormality diagnosis device determines whether an operational abnormality of the signal processing device exists based on a relationship between the sensor output signal and the control signal. A monitor IC monitors operational states of the torque monitor device and of the signal abnormality diagnosis device and determines whether an operational abnormality of the torque monitor device or of the signal abnormality diagnosis device exists.

Abstract: A vehicle monitoring system comprises a calculation module, an abnormal usage module, and memory. The calculation module calculates a vehicle usage value based on global positioning system (GPS) data and at least one data input, and calculates an expected vehicle usage value based on known vehicle characteristics and the GPS data. The abnormal usage module compares the vehicle usage value and the expected vehicle usage value. The memory stores an indicator based on the comparison.

Abstract: A method of controlling an engine in a motor vehicle includes opening a throttle to an increased angle when conditions for fuel cut cycling are met. More specifically, when cruise control is on, the motor vehicle is moving downhill, and the current speed drops below a target speed, the engine control unit may choose to increase the angle of the throttle while maintaining fuel cut. Under other interrupting events, the engine control unit may choose to resume fueling control or reduce the throttle angle.

Abstract: A vehicular electronic control apparatus includes a mother unit having a microcomputer, a plurality of ECU modules connected to the mother unit detachably and configured to execute respective vehicle controls, an operation data communication section for communicating with the microcomputer operation data used by the plurality of ECU modules in executing respective control operation processing, and alternative operation execution section for causing at least one of the other ECU modules and the microcomputer to execute, as an alternative operation, at least a part of the arithmetic operation processing, which is to be executed by at least one of the plurality of the ECU modules.

Abstract: A system for determining if a tire of a vehicle is improperly inflated. The system includes a radar, a wheel speed sensor, and a controller. The radar is configured to emit a signal generally parallel to a surface the vehicle is traveling on, to detect a reflection of the signal off of an object positioned perpendicular to the vehicle, and to output an indication of a speed of the vehicle. The wheel speed sensor is configured to sense a speed of a wheel of the vehicle. The controller is coupled to the radar and the wheel speed sensor, and is configured to receive the indication of the speed of the vehicle from the radar, to calculate a speed of the vehicle based on the sensed speed of the wheel, and to determine a tire of the wheel is improperly inflated when the speed of the vehicle calculated using the wheel speed sensor varies by more than a predetermined amount from the speed of the vehicle determined using the radar signal.

Abstract: Methods and apparatus are provided for analyzing a complex system that includes a number of subsystems. Each subsystem comprises at least one sensor designed to generate sensor data. Sensor data from at least one of the sensors is processed to generate binary evidence of a sensed event, and complex evidence of a sensed event. The complex evidence has more sophisticated mathematical properties than the binary evidence. The complex evidence comprises one or more of: a condition indicator (CI), a health indicator (HI), and a prognostic indicator (PI). A system fault model (SFM) is provided that defines statistical relationships between binary evidence, complex evidence, and an underlying failure mode (FM) that is occurring in the complex system. The binary evidence and the complex evidence are processed to identify failure modes taking place within one or more of the subsystems.

Abstract: A vehicle behavior data recording control system is disclosed. The system comprises a vehicle abnormality detector for detecting a vehicle abnormality and a recorder for acquiring vehicle abnormality information from the vehicle abnormality detector. In response to occurrence of an unexpected behavior, the recorder determines whether or not a cause of the unexpected behavior is the vehicle abnormality. When the cause of the unexpected behavior is the vehicle abnormality, the recorder is prohibited from recording a behavior data relating to the unexpected behavior. When the cause of the unexpected behavior is not the vehicle abnormality, the recorder records the behavior data relating to the unexpected behavior in the memory as an unexpected behavior data.

Abstract: An ECU executes a program including the steps of determining that a change speed solenoid is abnormal when a target speed ratio falls within a predetermined range, an upshift is recognized and the change speed solenoid is abnormal; determining that the change speed solenoid is normal when the change speed solenoid is not abnormal; determining that a belt pinch pressure solenoid is abnormal when the target speed ratio is substantially equal to a speed ratio ?min on a maximum speed-increase side and the target speed ratio is not substantially equal to an actual speed ratio; and determining that the belt pinch pressure solenoid is normal when the target speed ratio is substantially equal to the actual speed ratio.

Abstract: A yaw-rate forecasting system for a vehicle. The system includes a yaw rate sensor and an electronic control unit. The yaw rate sensor is configured to detect a yaw rate of the vehicle and to generate a signal indicative of the detected yaw rate. The electronic control unit is coupled to the yaw rate sensor, and is configured to receive the signal indicative of the yaw rate of the vehicle from the yaw rate sensor, forecast a future yaw rate, determine a stability of the vehicle using the forecasted yaw rate, and to generate a signal to control actuation of a vehicle brake.

Abstract: A method for monitoring the sensors in a vehicle control system. The method includes identifying a plurality of potential faults, identifying a plurality of measured values, and identifying a plurality of estimated values based on models in the control system. The method further includes identifying a plurality of residual error values as the difference between the estimated values and the measured values. The method also defines a plurality of fuzzy logic membership functions for each residual error value. The fuzzy logic membership functions are adaptive in that they change depending on the vehicle operating region, i.e., the non-linearity level of the vehicle, and the vehicle operating conditions, i.e., steady state verses transients. A degree of membership value is determined for each residual error value based on the membership functions. The degree of membership values are then analyzed in a fuzzy logic reasoning system to determine whether a potential fault exists.

Abstract: A gravity sensor (G-sensor) circuit system including a microcontroller that determines whether there is a failure in the G-sensor and, if it is determined that there is a failure in the G-sensor, outputs a failure signal to a controller outside the PCB, or the controller outside the PCB communicates with the G-sensor to determine whether there is a failure in the G-sensor, thus performing the self-diagnosis. The gravity sensor (G-sensor) circuit system performs self-diagnosis, zero-offset, and digital output, thereby using a more accurate sensor signal, improving the vehicle stability, and increasing the control precision and accuracy.

Abstract: The invention relates to a method for detecting an error in a component assembly of a motor vehicle, the component assembly having a functional control unit and at least one function module to be controlled by the functional control unit as components. According to the method, a check is made by the functional control unit to determine whether a combination of individual errors is present for at least one component of the component assembly. When the combination of individual errors is thereby present, an occurrence of the error is verified by the functional control unit and a signal for implementing an emergency functional strategy is transmitted by said control unit to an engine control unit.

Abstract: A hybrid electric vehicle (HEV) employing a hybrid system using both an internal combustion engine and a second motor/generator as a propelling power source for vehicle propulsion, and also employing a first generator driven by the engine for power generation, an integrated HEV control system is provided to control the engine, and the first and second motor/generators. The integrated HEV control system is also operable for detecting the presence of system failures and thereafter selecting at least one remedial action responsive to the system failures such that the system failures are corrected or minimized. The selected remedial action is also verified as being appropriate, monitored and thereafter executed.

Abstract: A method for monitoring a main control module operative to command first and second motor control processors of a hybrid powertrain system includes signally connecting a programmable logic device to the main control module and the first and second motor control processors, communicating a first seed signal from the programmable logic device to the main control module, and determining an invalid key signal in the main control module in response to the first seed signal. The invalid key signal is communicated to the programmable logic device.

Abstract: A driving recorder of the present invention is provided with: a data collecting portion that collects driving condition data of a vehicle; a storage portion that stores the driving condition data in a non-volatile manner; a communications portion that performs mutual communications with a mobile telephone terminal, using a cable or wirelessly; and a control portion that comprehensively controls these portions each provided as a functional part, wherein the control portion controls the communications portion to thereby permit the communications portion to transmit and receive the driving condition data to and from the mobile telephone terminal.

Abstract: A method for controlling an operating condition of a vehicle including executing, at each of operating cycles, at least one diagnostic phase applied to at least one computer controlling an operating condition of the vehicle, during which the computer produces and consumes data, at least one of the data capable of taking a particular predetermined value resulting from detection of an operating failure by the computer, so as to indicate a diagnostic result associated with the failure. The method stores, at the end of each cycle, the particular value for the failure concerned and initializes the diagnostic phase at the beginning of the next operating cycle with the stored particular data so as to reproduce, for the failure concerned, the diagnostic result supplied by the diagnostic phase when it was last executed.

Abstract: In a method for identifying a defective control device in an internal combustion engine, especially a control element of an intake manifold with a variable length, a swirl flap, or a tumble flap, or generally a control element in the air path of the internal combustion engine, instead of using a return message acknowledging the position of the control device, a regulating signal is detected following the successful switching of the control device, in order to use any deviations of said regulating signal above a defined threshold value to identify a defective control device.

Abstract: A method and device for detecting oscillatory faults relating to an aircraft airfoil slaving chain. The device includes units that count the number of overshoots of a threshold value by the current value of a quantity related to the positional slaving of an airfoil. Oscillatory fault is detected based on the number of overshoots of the threshold value being greater than the current value by a predetermined number.

Abstract: To provide a vehicle electronic control unit including a first microcomputer (2, 3) and a second microcomputer (3, 2) capable of transmitting and receiving signals to and from the first microcomputer. One of the first microcomputer and the second microcomputer outputs a PWM signal to the other microcomputer (3, 2). The other microcomputer detects an on-time of the PWM signal, performs a self diagnosis according to the detected on-time, and outputs a self diagnosis result to the one microcomputer. The one microcomputer diagnoses the other microcomputer based on the self diagnosis result.

Abstract: An electric power steering system of a vehicle has a plurality of Hall ICs for sensing torque applied to a steering wheel, and an electric motor for power-assisting the steering wheel. A supply voltage for the Hall ICs is varied temporarily to check the electric output signals of the Hall ICs. A non-failing device of the plurality of Hall ICs, which generates the electric output signal varying in response to the variation of the supply voltage, is selected. The electric motor is controlled based on only the electric output signal of the non-failing device.

Abstract: In an electric power steering system, an electric motor generates output power for power-assisting steering operation of a steering wheel, a torque sensor generates a plurality of electric output signals corresponding to a torque applied to the steering wheel, and a control unit controls the steering operation of the electric motor in accordance with at least one of the electric output signals of the torque sensor. The control unit detects a difference between rotation speeds of left and right steered wheels, checks whether any one of the plurality of output generating parts is in failure, and specify a failing-device based on the rotation speed difference and the plurality of output signals.

Abstract: A system for adjusting a wheel lock angle of a wheel of a motor vehicle, in particular of a rear wheel, wherein at least one wheel guide member, by means of which a wheel carrier of the wheel is connected to a vehicle body, wherein the wheel carrier can pivot about a rotational axis which runs substantially parallel to the plane of the wheel and the wheel guide member is coupled to the wheel carrier at a distance from the rotational axis, and wherein the length of the wheel guide member can be adjusted by an actuator, wherein at least one actuator is driven by a motor and at least one control unit, and the control unit includes a computer unit with a memory and a communication interface, and the control unit transmits and receives data via the communication interface by means of at least one communication bus.

Abstract: Fault diagnosis logic of a fuel filter heater may include a microprocessor electrically connected with the fuel filter heater, applying ground voltage to a power supply terminal of the fuel filter heater when an ignition switch turns on and a fuel filter relay turns on, measuring resistance of the fuel filter heater, and determining whether or not the fuel filter heater fails according to whether a measured resistance of the fuel filter heater is within a predetermined range or not.

Abstract: A diagnostic device of an internal combustion engine diagnoses a condition of a differential pressure sensor. The sensor in a normal condition detects a differential pressure of an exhaust gas between upstream and downstream sides of a diesel particulate filter disposed in an exhaust system of the engine. The sensor in a fault condition detects no differential pressure of the exhaust gas. The device has a block obtaining a first signal from the sensor when the engine is operated in a low flow rate region of the exhaust gas and obtaining a second signal from the sensor when the engine is operated in a high flow rate region of the exhaust gas. A diagnostic block of the device judges from a difference between levels of the first and second signals whether the sensor is in the normal or fault condition.