Abstract: The present disclosure relates to a thermostat fault diagnosis method. The method includes: a current environment temperature and a boundary temperature and initial opening temperature corresponding to the current environment temperature are acquired; engine thermal equilibrium state data determined based on coolant temperature change data in an engine are acquired; a current coolant temperature is acquired; and according to the engine thermal equilibrium state data and a relationship between the current coolant temperature and the boundary temperature and initial opening temperature, it is judged whether a thermostat is faulty.

Abstract: A sensing apparatus measures the disk tilt angle of a swing or tilting disk check valve without requiring penetration of the valve housing through a rotating shaft seal. A hinge pin extension is rotationally coupled to the valve disk, and a mechanical converter converts rotation thereof into translation of a magnet carrier within a non-magnetic extension of the valve housing. An LVDT core magnet is translated by the magnet carrier within the housing extension while surrounded by LVDT sensor coils mounted to the exterior of the housing extension. The LVDT core magnet and sensor coils thereby provide an LVDT output signal that indicates the tip angle of the valve disk. Embodiments include threaded coupling of the hinge pin extension to the magnet carrier, or coupling therebetween by a converter pin fixed to one of them into angled helical slot of a cylinder fixed to the other of them.

Abstract: The present invention relates to a method for monitoring a base device (11), in particular a building or part of a building or a vehicle, by means of a mobile terminal (10), wherein the base device (11) has at least one heating device, in particular with a temperature sensor, comprising the steps: determining a current state of the base device (11) by means of the heating device, in particular comprising determining a current temperature at or in the base device (11) by the temperature sensor of the heating device and/or determining an energy supply of the heating device, checking whether the current state is a normal state or an abnormal state and/or whether the current change in state is a normal change in state or an abnormal change in state, and outputting of corresponding information to the mobile terminal (10) and/or by said mobile terminal, at least when an abnormal state and/or an abnormal change in state is detected.

Abstract: A control device for a hybrid vehicle, includes a travel route creation unit creating a travel route from a starting point to a destination through a stopping point by referring to map information; a parking time period estimation unit estimating a parking time period of the hybrid vehicle at the stopping point; a travel load prediction unit predicting a traveling load of the hybrid vehicle in each of sections obtained by dividing the travel route by referring to the map information; and a travel mode setting unit setting, for each of the sections, a traveling mode of an EV mode, in which the battery provides power for traveling as a main power supply, or an HV mode, in which the internal combustion engine provides the power for traveling as the main power supply, on the basis of the parking time period and the traveling load.

Abstract: A method of diagnosing a mechanical coolant pump in an automobile equipped with cooling system having a mechanical coolant pump and an electric coolant pump comprises detecting when an engine of the automobile has been started, dis-engaging the electric coolant pump, engaging the mechanical coolant pump, and verifying the mechanical coolant pump is operating properly.

Abstract: A control method for a cooling system is provided. The method includes determining whether the output signals of a first coolant temperature sensor and a second coolant temperature sensor satisfy a predetermined coolant overheating condition. A coolant control valve unit is operated to move the cam to a maximum position when the predetermined coolant overheating condition is satisfied. Additionally, a control temperature is determined according to an output signal of the first coolant temperature sensor and the second coolant temperature sensor and an operation of the injector is limited according to the determined control temperature.

Abstract: A bilge pump monitoring system for a bilge pump on a marine vessel includes a current sensor configured to measure a current draw of the bilge pump, and a bilge pump monitor module executable on a processor. The bilge pump monitor module is configured to receive current draw measurements by the current sensor and determine a pump diagnosis of the bilge pump based on the current draw measurements. The pump diagnosis is then wirelessly communicated to a user located remotely from the marine vessel.

Abstract: A method for diagnosing the absence of an under-engine protection of a motor vehicle, includes: estimating a temperature of air external to the vehicle, estimating an under-hood temperature, determining whether the external-air temperature value is below the under-hood temperature value, in the affirmative, calculating an absolute value of a difference between the external-air temperature measurement and the under-hood temperature measurement, determining a diagnostic criterion by calculating a difference between the absolute value and a predetermined absolute value, obtained in the presence of the under-engine protection, comparing the diagnostic criterion against a predetermined diagnostic threshold, and emitting a diagnostic signal dependent on the result of the comparison.

Abstract: This thermostat abnormality determining device includes a cooling water temperature sensor, an estimated temperature calculating unit and a determining unit. The cooling water temperature sensor detects the temperature of cooling water that cools an engine. The estimated temperature calculating unit calculates an estimated temperature, which is an estimated value of the temperature of the cooling water. The determining unit determines if the thermostat has become stuck open after warming-up of the engine is complete.

Abstract: A pressure relief valve is opened from a first time to a second time for the purpose of reducing the pressure in the gas phase in a gas-liquid separator. A first water pump (WP) is driven at a third time and a fourth time. The third time and fourth time correspond to timings at which a difference between a boiling temperature and an actual temperature becomes equal to or greater than a predetermined temperature. Since liquid-phase coolant in a catch tank can be fed to another water pump by driving the first WP, the actual temperature of the liquid-phase coolant immediately upstream of the other water pump can be lowered. It is thus possible to prevent intense boiling of the liquid-phase coolant immediately upstream of the other water pump.

Abstract: A thermostat is diagnosed as open failure when a specified time variation in radiator inflow water temperature from a temperature sensor mounted in a first flow path running through a radiator at a time of starting an electric water pump at a cold start of an engine is equal to or greater than a predetermined variation. In the case of open failure of the thermostat, starting the electric water pump causes cooling water from a cooling water flow path of the engine to be flowed to the first flow path, as well as to a second flow path. The radiator inflow water temperature detected by the temperature sensor mounted in the first flow path is raised by the cooling water from the cooling water flow path of the warmed engine.

Abstract: Methods are provided for engine coolant system diagnostics. In one example, engine coolant system malfunction is indicated based on an engine coolant temperature inference model, whereas in another example engine coolant system malfunction is indicated based on a time-based monitor, where the inference model is enabled at ambient temperatures above a predetermined threshold, and where the time-based monitor is enabled at ambient temperatures below the predetermined threshold. In this way, accurate engine coolant system diagnosis may be accomplished under ambient temperature conditions wherein the engine coolant temperature inference model may be compromised.

Abstract: Methods and systems are provided for a vehicle comprising, during a first condition comprising when an active grille shutter (AGS) position change over a second interval is less than a threshold position change: stalling an AGS motor for a first interval; calculating a fuel economy change over the first interval; and determining a degradation of an AGS sensor based on the fuel economy change being greater than a threshold fuel economy change over the first interval. In this way, various degradation modes of the AGS including faulty AGS position sensors and a mechanical AGS degradation can be differentiated. Furthermore, in the event of an AGS position sensor degradation, the AGS position can be inferred so that operation of the AGS and the fuel consumption reduction advantages conferred therefrom can be preserved.

Abstract: A cooling water control apparatus controls a cooling apparatus having first pipe which circulates cooling water through an engine; second pipe which circulates cooling water not through the engine; a switching valve whose state is changed between opened and closed states; and a supplying mechanism which supplies cooling water, and has a determining device which determines whether there is failure of the switching valve based on difference between first temperature of cooling water in first pipe and second temperature of cooling water in second pipe after the command for changing the state of the switching valve from closed state to opened state is outputted; and a controlling device which controls the supplying mechanism to supply cooling water even after the engine stops, when the engine stops while the determining device determines whether there is failure of the switching valve.

Abstract: An apparatus for determining a failure in a thermostat for controlling the flow of a coolant into a radiator in response to an actual water temperature of the coolant for an engine in a vehicle includes: a water temperature detector that detects the actual water temperature; a water temperature estimator that calculates an estimated water temperature of the coolant; and a failure determining unit that compares the actual water temperature detected by the water temperature detector with the estimated water temperature calculated by the water temperature estimator under cold start of the engine and determines whether the thermostat is valve-open failure. In an engine nonoperating mode including at least automatic stop of the engine, the water temperature estimator applies a behavior of the actual water temperature to an estimated water temperature calculated immediately before automatic stop of the engine to calculate an estimated water temperature in the engine nonoperating mode.

Abstract: Various methods and systems are provided for estimating a wall temperature in a heat exchanger and reducing the risk of boiling on a coolant side of the heat exchanger. In one embodiment, a method for an engine comprises estimating a wall temperature at a location in a heat exchanger and adjusting an engine operating parameter of an engine coupled to the heat exchanger based on the wall temperature.

Abstract: Methods and systems are provided for expediting engine system heating by stagnating coolant in one of a plurality of loops in an engine cooling system. Degradation of the various valves and thermostats of the cooling system can be diagnosed by adjusting the valve and monitoring changes in one or more of coolant temperature, transmission temperature and cabin temperature. Based on engine operating conditions, the various valves may be adjusted to vary coolant temperature in different regions of the cooling system, thereby providing fuel economy benefits.

Abstract: A universal fitting for in-line fluid measurement in a process application. The fitting including an inlet and outlet port. The fitting also having a body with a fluid flow passage providing fluid communication between the ports. A sensor housing is provided that extends outwardly away from a wall of the body, wherein the housing is sized to receive a sensor assembly, which assembly measures at least one characteristic of the fluid. A base of each housing integrally formed with the wall and including a sensor seat for receiving a portion of the sensor assembly. A probe aperture receives a probe portion of the sensor assembly, each housing having the probe aperture disposed in the wall and extending from the fluid passage through its respective sensor seat.

Abstract: Methods and systems are provided for diagnosing each of a plurality of engine cooling system components including various valves and grill shutters. Each valve may be individually closed and opened for a specified duration, and corresponding changes in coolant temperature may be monitored. If all the components are functional, the various valves may be adjusted to stagnate coolant at the engine and expedite engine warm-up during a cold-start.

Abstract: A fan simulation circuit includes a connector, a voltage converter, a control chip, and a selecting module. The connector is used to output a speed signal. A power pin of the voltage converter is connected to a first voltage input terminal. An output pin of the voltage converter is connected to a speed pin of the connector through a first resistor. The output pin is also connected to a second voltage input terminal through the first resistor and a second resistor in that order. The selecting module is used to output high or low-level signals to the control chip. The control chip outputs different speed signals to an input pin of the voltage converter. The voltage converter converts the speed signals and outputs converted speed signals to the speed pin of the connector.

Abstract: A coefficient value acquiring unit acquires values of coefficients C and K representing a relationship among a heat generation amount of a motor generated due to a loss Q1(t) of the motor, a temperature variation amount of the motor, and a placement position of a temperature detection device, using the loss Q1(t) of the motor, a detection temperature Td(t), and an ambient temperature Ta of the motor. The temperature estimating unit estimates a temperature Te(t) of the motor based on the values of the coefficients C and K, a preset reference value Cm of the coefficient C, a preset reference value Km of the coefficient K, the detection temperature Td(t), and the ambient temperature Ta of the motor.

Abstract: A cooling pipe for an internal combustion engine includes with a resin-made water outlet for forming a circulation path for circulating a coolant for cooling an engine body, and an attachment part for retaining a water temperature sensor for sensing the temperature of the coolant flowing through the water outlet, the attachment part being attached to the water outlet, a portion of the attachment part being in contact with the engine body, and the attachment part formed from a material whereby heat from the engine body is transmitted.

Abstract: An ECU sets a leakage flow rate flowing through a radiator circulation passage in a closed state of a thermostat valve, calculates an estimated temperature of coolant water in the radiator circulation passage based on a set leakage flow rate and a detected water temperature of an engine-side coolant water temperature sensor, and performs a failure diagnosis for the thermostat valve based on a difference between the calculated estimated temperature and the detected water temperature of the radiator-side coolant water temperature sensor. The leakage flow rate during operation of the electric pump is set to be a larger value as compared to the leakage flow rate during stopping of the pump. As a result, a diagnostic can be prevented by improving an accuracy of failure detection for the thermostat valve.

Abstract: A diagnostic test is conducted by operating an engine-generator set at a plurality of reduced speeds. At each of those speeds, operating parameters of the engine are sensed and analyzed to detect an unsatisfactory operating condition. For example, such operating parameters may include speed of the engine-generator set, engine oil pressure and level, engine temperature, coolant level, and battery voltage. When a transition in engine speed occurs, a throttle test also may be conducted to measure how quickly and smoothly the engine reaches the new speed. After the engine reaches the normal operating speed, the generator is activated to produce electricity. One or more characteristic of that electricity, such as voltage, current and frequency, are sensed and evaluated to detect an unsatisfactory operating condition.

Abstract: A method for determining a velocity of headwind flowing in the direction of a vehicle, based on a coolant mass flow of a coolant flowing through a heat exchanger of a cooling device of the vehicle, and an air mass flow flowing through the heat exchanger and triggered by the headwind, includes: determining a temperature drop of the coolant mass flow; determining the air mass flow responsible for the temperature drop of the coolant mass flow; and determining the velocity of the headwind flowing in the direction of the vehicle, based on the air mass flow responsible for the temperature drop of the coolant mass flow.

Abstract: In a method and a device for diagnosing a switchable coolant pump for circulating a coolant in a coolant circuit of an internal combustion engine, an actual value of the cylinder head temperature of the internal combustion engine is measured and the actual value of the cylinder head temperature is compared with a model value of the cylinder head temperature. The functionality of the coolant pump is assessed according to the comparison result.

Abstract: A method of diagnosing a cooling subsystem of an engine system in response a parameter extracted from dynamic hydraulic pressure sensed in the cooling subsystem, and products and systems using same.

Abstract: A malfunction determination apparatus for a cooling apparatus that cools an internal combustion engine by circulating a coolant through an interior of the internal combustion engine, using an electric pump, after the internal combustion engine is started includes: a detection portion that detects the coolant temperature; and a determination portion that determines a malfunction has occurred in a thermostat, if a state in which the detected coolant temperature remains below a first threshold temperature after the electric pump begins operating, following start of the internal combustion engine, continues for at least a pre-determined time. The thermostat is a thermostat for switching from a first passage for circulating the coolant without passage via an interior of a radiator of the cooling apparatus to a second passage for circulating the coolant via the interior of the radiator, as the coolant temperature rises.

Abstract: A system includes a pump control module and a pump diagnostic module. The pump control module switches a switchable water pump from off to on. The pump diagnostic module diagnoses a fault in the switchable water pump based on a first difference between an engine material temperature and an engine coolant temperature when the switchable water pump is switched from off to on. The engine coolant temperature is a temperature of coolant circulated through an engine and the engine material temperature is a temperature of at least one of an engine block and a cylinder head.

Abstract: An abnormality detection apparatus for a Rankine cycle system includes: a gas-liquid separator that separates a cooling medium that circulates in an internal combustion engine into a gas-phase and a liquid-phase; a superheater that gives waste heat of the engine to the cooling medium; a waste heat recoverer that recovers energy of waste heat of the cooling medium; a valve provided in a passageway; a liquid surface sensor that detects liquid surface level of the liquid-phase cooling medium in the gas-liquid separator; a vapor temperature sensor that detects temperature of the gas-phase cooling medium in the superheater; and an ECU that determines whether the valve is abnormal on the basis of the amount of the liquid-phase cooling medium and the temperature of the gas-phase cooling medium if abnormality of the cooling medium supply portion of the engine is not detected.

Abstract: A thermostat diagnostic apparatus is provided with a cooling medium temperature sensor, an engine operating condition sensor and a malfunction diagnosing device. The malfunction diagnosing device is configured to diagnose a stuck-open malfunction of a thermostat provided in a coolant flow passage of an engine installed in a mobile body based on a comparison of a real cooling medium temperature detected by the cooling medium temperature sensor and an estimated cooling medium temperature estimated based on an engine operating condition of the engine detected by the engine operating condition sensor. The malfunction diagnosing device determines that the thermostat is stuck in an open state upon determining that either the estimated cooling medium temperature or the real cooling medium temperature exceeds a prescribed reference value during a period in which an increased heat exchange rate condition of a radiator is satisfied continuously.

Abstract: A fan coupling device 1 connecting an internal combustion engine 31 to a cooling fan 21 comprises an input shaft 3 driven to rotate by the engine 31, a fluid coupling 12 that transmits torque from the input shaft 3 to the cooling fan 21 via a fluid, and a solenoid valve 13 having a valve main body 18 that adjusts a fluid amount in the fluid coupling 12. A determination as to whether or not the valve main body 18 is stuck in a lifted position on the basis of a rotation speed of the cooling fan 21, is started after the elapse of a predetermined time following output of a signal for returning the valve main body 18 to a closed position, The sticking determination can be performed with a high degree of precision without being affected by variation in the rotation speed of the input shaft 3.

Abstract: Methods and systems are provided for diagnosing each of a plurality of engine cooling system components including various valves and grill shutters. Each valve may be individually closed and opened for a specified duration, and corresponding changes in coolant temperature may be monitored. If all the components are functional, the various valves may be adjusted to stagnate coolant at the engine and expedite engine warm-up during a cold-start.

Abstract: Methods and systems are provided for diagnosing each of a plurality of engine cooling system components including various valves and grill shutters. Each valve may be individually closed and opened for a specified duration, and corresponding changes in coolant temperature may be monitored. If all the components are functional, the various valves may be adjusted to stagnate coolant at the engine and expedite engine warm-up during a cold-start.

Abstract: A competence diagnosis system for a urea water temperature sensor that can limit a diagnosis during a cold start. The system includes a cold start condition determination unit that obtains a difference between an engine cooling water temperature and an ambient temperature, a difference between an engine cooling water temperature and a fuel temperature, and a difference between an ambient temperature and a fuel temperature by using an engine cooling water temperature, an ambient temperature, and a fuel temperature measured immediately after engine starting, and allows a diagnosis by the competence diagnosis unit when the temperature differences are less than or equal to a predetermined threshold value.

Abstract: Methods and systems are provided for expediting engine system heating by stagnating coolant in one of a plurality of loops in an engine cooling system. Degradation of the various valves and thermostats of the cooling system can be diagnosed by adjusting the valve and monitoring changes in one or more of coolant temperature, transmission temperature and cabin temperature. Based on engine operating conditions, the various valves may be adjusted to vary coolant temperature in different regions of the cooling system, thereby providing fuel economy benefits.

Abstract: An abnormality detection apparatus for a Rankine cycle system includes: a main body that vaporizes a cooling medium that circulates in an internal combustion engine by giving waste heat to the cooling medium; a gas-liquid separator that separates the cooling medium into a gas-phase and a liquid-phase; a superheater that gives waste heat of the engine to the cooling medium; a condensate header tank that stores the liquid-phase cooling medium; a vane pump that pumps the liquid-phase cooling medium. If abnormality of a cooling medium supply portion that supplies the cooling medium to the engine is not detected, the abnormality detection apparatus determines whether a vane pump has abnormality on the basis of the amount of the liquid-phase cooling medium in the gas-liquid separator, the temperature of the gas-phase cooling medium in the superheater and the amount of the liquid-phase cooling medium in the condensate header tank.

Abstract: An abnormality detection apparatus for a Rankine cycle system includes: a gas-liquid separator that separates a cooling medium that circulates in an internal combustion engine into a gas-phase and a liquid-phase; a superheater that gives waste heat of the engine to the cooling medium; a waste heat recoverer that recovers energy of waste heat of the cooling medium; a valve provided in a passageway; a liquid surface sensor that detects liquid surface level of the liquid-phase cooling medium in the gas-liquid separator; a vapor temperature sensor that detects temperature of the gas-phase cooling medium in the superheater; and an ECU that determines whether the valve is abnormal on the basis of the amount of the liquid-phase cooling medium and the temperature of the gas-phase cooling medium if abnormality of the cooling medium supply portion of the engine is not detected.

Abstract: An abnormality detection apparatus for a Rankine cycle system includes: a main body that vaporizes a cooling medium that circulates in an internal combustion engine by giving waste heat to the cooling medium; a gas-liquid separator that separates the cooling medium into a gas-phase and a liquid-phase; a superheater that gives waste heat of the engine to the cooling medium; a condensate header tank that stores the liquid-phase cooling medium; a vane pump that pumps the liquid-phase cooling medium. If abnormality of a cooling medium supply portion that supplies the cooling medium to the engine is not detected, the abnormality detection apparatus determines whether a vane pump has abnormality on the basis of the amount of the liquid-phase cooling medium in the gas-liquid separator, the temperature of the gas-phase cooling medium in the superheater and the amount of the liquid-phase cooling medium in the condensate header tank.

Abstract: A method for determining a velocity of headwind flowing in the direction of a vehicle, based on a coolant mass flow of a coolant flowing through a heat exchanger of a cooling device of the vehicle, and an air mass flow flowing through the heat exchanger and triggered by the headwind, includes: determining a temperature drop of the coolant mass flow; determining the air mass flow responsible for the temperature drop of the coolant mass flow; and determining the velocity of the headwind flowing in the direction of the vehicle, based on the air mass flow responsible for the temperature drop of the coolant mass flow.

Abstract: A control device may include an actuator for actuating a final control element on a cooling system of an internal combustion engine and a sensor for scanning a position of the final control element. A method for checking the control device may include the steps of triggering the actuator with a predetermined control signal, determining a progression of the control position scanned by the sensor, and determining the functional capability of the mechanical coupling of the actuator to the final control element on the basis of the predetermined control signal and the determined progression.

Abstract: In a malfunction determination apparatus and a malfunction determination method for a cooling apparatus that cools an internal combustion engine by circulating a cooling medium that flows in a first passage that extends through an inside of the engine, using an electric pump, a first temperature of the cooling medium is detected at an inlet of the first passage, through which the cooling medium flows into the inside of the engine; a second temperature of the cooling medium is detected at an outlet of the first passage, through which the cooling medium flows out from the inside of the engine; and it is determined that the switching valve is able to normally select the second passage, if both of the first temperature and the second temperature reach a first threshold value when a temperature of the cooling medium increases due to start of the engine.

Abstract: A radiator grille tester of the present invention includes two adapters, a transparent tube, and a detector. The transparent tube and the detector are located between the adapters. The adapters, the transparent tube, and the detector are serial connected and define a channel. The adapters can be connected to an engine and a radiator respectively. Therefore, water in the engine and the radiator can flow passing through the transparent tube and the detector via the adapter. User can observe the water flow directly so as to check whether the engine and the radiator are malfunctioned. Observation and examination procedures are simplified.

Abstract: A system and method for determining whether a shut-off valve in a cabin heating by-pass line of a thermal sub-system associated with an engine has failed that uses the pump current for a pump that pumps the cooling fluid through the by-pass line. The method includes setting a predetermined constant speed of the pump and then providing a valve command that opens the by-pass valve. The method then determines if the pump current has increased or remained substantially the same when the by-pass valve is commanded open, and determines that the by-pass valve has not opened if the pump current remains substantially constant when the by-pass valve is commanded open.

Abstract: A competence diagnosis system for a urea water temperature sensor that can limit a diagnosis during a cold start. The system includes a cold start condition determination unit that obtains a difference between an engine cooling water temperature and an ambient temperature, a difference between an engine cooling water temperature and a fuel temperature, and a difference between an ambient temperature and a fuel temperature by using an engine cooling water temperature, an ambient temperature, and a fuel temperature measured immediately after engine starting, and allows a diagnosis by the competence diagnosis unit when the temperature differences are less than or equal to a predetermined threshold value.

Abstract: A radiator grille tester of the present invention includes two adapters, a transparent tube, and a detector. The transparent tube and the detector are located between the adapters. The adapters, the transparent tube, and the detector are serial connected and define a channel. The adapters can be connected to an engine and a radiator respectively. Therefore, water in the engine and the radiator can flow passing through the transparent tube and the detector via the adapter. User can observe the water flow directly so as to check whether the engine and the radiator are malfunctioned. Observation and examination procedures are simplified.

Abstract: An onboard cooling system diagnostic strategy utilizes at least one temperature sensor fluidly positioned between an electronically controlled engine and a thermostat. The diagnostic algorithm operates by monitoring coolant temperature during engine startup. By comparing the actual coolant temperature during engine start-up to a predicted coolant temperature that should occur if no cooling system error is present, a cooling system fault condition may be identified. If a cooling system fault is detected, the diagnostic logic may activate the engine cooling fan or intrusively open an electrically controlled thermostat while monitoring the coolant temperature response to the intrusive action. If there is a substantial change in coolant temperature responsive to the intrusive action, this phenomenon can be utilized to correctly distinguish between a thermostat failure and a vehicle configuration error corresponding to an overcooled vehicle.

Abstract: A product, which passages are to be checked is brought to the measuring position, at least one measuring probe containing at minimum one emitting element and at minimum one receiving element is moved toward or inserted into openings of the product passages or an assembly of measuring probes consisting of at minimum one measuring probe containing at minimum one emitting element and at minimum one measuring probe containing at minimum one receiving element is moved toward or inserted into the opening of the product passages, following the part of the assembly consisting of at minimum one measuring probe containing at minimum one emitting element emitting in range of visible spectrum and/or infrared spectrum in the region of wavelength from 400 nm to 1500 nm is turned on and on the measuring probe, containing the receiving element, that forms a pair with the just working emitting element a response—a signal, size of which depends on amount of passed light, is measured, a signal amount is analysed and compared wi

Abstract: An engine coolant amount determining apparatus includes an electric water pump that can be operated intermittently while an engine is running, and a coolant temperature detecting means for detecting the temperature of coolant at a location higher than the water pump. The engine coolant amount determining apparatus also includes determining means for determining that the amount of coolant is equal to or less than a predetermined amount when the degree of change in the coolant temperature detected by the coolant temperature detecting means when the water pump is operated intermittently is large.

Abstract: A fan coupling device 1 connecting an internal combustion engine 31 to a cooling fan 21 comprises an input shaft 3 driven to rotate by the engine 31, a fluid coupling 12 that transmits torque from the input shaft 3 to the cooling fan 21 via a fluid, and a solenoid valve 13 having a valve main body 18 that adjusts a fluid amount in the fluid coupling 12. A determination as to whether or not the valve main body 18 is stuck in a lifted position on the basis of a rotation speed of the cooling fan 21, is started after the elapse of a predetermined time following output of a signal for returning the valve main body 18 to a closed position, The sticking determination can be performed with a high degree of precision without being affected by variation in the rotation speed of the input shaft 3.