Abstract: A head-up display system embedded in a vehicle having at least one tire is provided. The head-up display system includes a tire sensor, a speed detecting module, a host apparatus and a head-up display apparatus. The tire sensor is disposed within the tire for detecting a temperature and a pressure of the tire, and the speed detecting module detects a speed of the vehicle. The host apparatus drives the tire sensor with a wireless low-frequency signal and receives a high-frequency temperature signal and a high-frequency pressure signal transmitted from the tire sensor. Afterwards, according to the received signals, a processing unit of the host apparatus drives the head-up display apparatus to produce a temperature image, a pressure image and a speed image on a windshield by projecting.

Abstract: A method for determining a steady state operating condition of a machine includes determining whether a current machine speed of the machine is within a defined range of operation, determining whether a step change in output power of the machine has occurred, determining a first duration of time elapsed since the machine speed was last outside of the defined range of operation, and determining a second duration of time elapsed since a most recent detected step change in output power of the machine. The machine is deemed to be in a steady state condition whenever the current machine speed of the machine is within said defined range of operation, and the first and second durations of time exceed respective minimum values defined therefor.

Abstract: The present invention provides a tire pressure sensor system that has multiple functions and is integrated into a small package. The system includes one or more Micro Electro Mechanical System (MEMS)-based sensors, including a MEMS-based pressure sensor; a MEMS-oscillator-based wireless signal transmitter; and a microcontroller, where the microcontroller processes the data generated by at least one of the MEMS-based sensors, controls at least one of the MEMS-based sensors, and controls the encoding and timing of transmission of data from the wireless signal transmitter. Preferably, the MEMS-based sensors, MEMS-oscillator-based wireless signal transmitter, and microcontroller are integrated onto one or more chips in one or more packages. The system also preferably includes a MEMS-based motion sensor, a low frequency (LF) receiver, an IC-based voltage sensor, a voltage regulator, a temperature sensor and a polarization voltage generator.

Abstract: A tire monitoring system for a vehicle having tires determines if two tires share a same side of the vehicle based on a state of each of the two tires. In at least one embodiment, a first output signal indicative of a state of a first tire and a second output signal indicative of a state of a second tire are transmitted and received. A determination as to whether the first tire and the second tire are on a same side of the vehicle based on the state of the first tire and the state of the second tire is made.

Abstract: A tire pressure monitoring system may adjust the power it consumes. In at least one embodiment, the system includes a receiver that receives a first signal having a signal strength, determines the signal strength, and causes a second signal to be sent if the signal strength is more than a desired signal strength.

Abstract: In order to develop an electronic communication system (100; 100?), designed for a progressive movement means, having at least one base station (10) and having at least one carrier station (60) such that the possible uses of this communication system (100; 100?) can also be extended to other important areas of use of a progressive movement means, it is proposed that the carrier station (60) be designed as in each case at least one sensor unit, which is assigned to at least one wheel or tire (90) of the progressive movement means and—which is designed to detect and/or determine at least one characteristic parameter of the wheel or tire (90), such as for example the air pressure and/or the temperature and/or the wear of the wheel or tire (90).

Abstract: The system includes a carbon dioxide sensor, a temperature sensor and a controller. The carbon dioxide sensor is in electrical communication with the controller and generates a carbon dioxide signal indicative of the carbon dioxide level contained in the air within the vehicle cabin. The temperature sensor is also in electrical communication with the controller and generates a temperature signal indicative of the temperature within the vehicle cabin. The controller is configured to initiate a safety precaution based on the carbon dioxide signal and the temperature signal.

Abstract: A tension control assembly including a rotating member, a braking member, at least one brake pad, a means for driving the at least one brake pad against the braking member, and a temperature sensing means. The braking member is attached to the rotating member. The at least one brake pad is positioned adjacent to the braking member. The means for driving the at least one brake pad against the braking member forces frictional contact between the at least one brake pad and the braking member, thus providing torque to the rotating member. The temperature sensing means measures the temperature of the at least one brake pad.

Abstract: A method of detecting a rapid leak of gas contained in an automobile tire based on periodic measurements of a pressure Pa and a temperature Ta of the gas. The method includes determining a reference pressure Pcref, calculating an alarm threshold pressure Sref from the reference pressure Pcref, calculating a temperature-compensated pressure Pc at each measurement acquisition period, and comparing the compensated pressure Pc with the alarm threshold pressure Sref, wherein the leak is detected if the compensated pressure Pc is less than the alarm threshold pressure Sref.

Abstract: A control system is employed in a vehicle to assist a user to operate the vehicle effectively and safely. In accordance with the invention, the system provides driving assistance to the user by taking into account the user's physical condition, the vehicle condition and the surrounding conditions. The surrounding conditions include, e.g., road, weather and traffic conditions, external to the vehicle. The vehicle condition concerns the conditions of the brakes, steering, tires, radiator, etc. of the vehicle. Signs of fatigue, stress and illness of the user are monitored by the control system to assess the user's physical condition.

Abstract: A tire-information administration system includes a plurality of sensor modules installed in tires; at least one reception module configured to receive data from the sensor modules; and a central control module configured to command the reception module to acquire data from the sensor modules. The central control module includes a predetermined number of connection ports for the reception module, assigned in advance to each sensor modules; and a specifically configured control means.

Abstract: The present invention provides a system, method and apparatus for reducing a vehicle driver's core temperature to offset drowsiness. In one embodiment, a temperature sensor records data describing a vehicle driver core temperature and communicates the data describing the vehicle driver core temperature to a temperature regulator. The temperature regulator determines whether the vehicle driver core temperature is similar to one or more circadian temperatures associated with wakefulness. If the vehicle driver core temperature is similar to a circadian temperature associated with sleep, the temperature regulator reduces the vehicle driver core temperature. In an embodiment the temperature regulator cools a material physically contacting the venous plexuses or arteriovenous anastomoses to cool the portions of the vehicle driver's anatomy which most efficiently cool the vehicle driver.

Abstract: The invention relates to an operating element for a heating and air conditioning system for the setting of air conditioning parameters in a vehicle interior, the setting being fed back to the operator of the operating element. In order to provide an operating element for a heating and air conditioning system, for the operating of which the attention of the vehicle driver is demanded as little as possible, the feedback of the set air conditioning parameters to the operator takes place by means of the operating element itself.

Abstract: The invention relates to an engine cooling system monitoring system. There is a need for a cooling system monitoring system for an engine system wherein the coolant is maintained at a precise temperature. Thus, a cooling system monitoring system is provided for an engine system having internal combustion engine, a fan driven by a variable speed fan drive, and a radiator for cooling coolant circulating through the engine. The monitoring system includes a fan speed sensor generating a fan speed signal, a control unit and a display device controlled by the control unit. The control unit generates a cooling system status signal as a function of the fan speed signal and a maximum fan speed value. The display device has visible position range associated with a normal engine operating temperature, and has an indicator movable within said position range in response to the cooling system status signal to indicate a status of the engine cooling system.

Abstract: The invention relates to an engine cooling system monitoring system. There is a need for a cooling system monitoring system for an engine system wherein the coolant is maintained at a precise temperature. Thus, a cooling system monitoring system is provided for an engine system having internal combustion engine, a fan driven by a variable speed fan drive, and a radiator for cooling coolant circulating through the engine. The monitoring system includes a fan speed sensor generating a fan speed signal, a control unit and a display device controlled by the control unit. The control unit generates a cooling system status signal as a function of the fan speed signal and a maximum fan speed value. The display device has visible position range associated with a normal engine operating temperature, and has an indicator movable within said position range in response to the cooling system status signal to indicate a status of the engine cooling system.

Abstract: An electronic vehicle tester includes a battery tester configured to measure a parameter of a battery of a vehicle. A tire tester is configured to receive a parameter of a tire of the vehicle. A wireless receiver can be configured to receive pressure information from a transmitter associated with a tire of a vehicle.

Abstract: A transmitter module has a sensor module that includes a plurality of sensors and operates intermittently, a signal processor module that permits transmission of an output of the sensor module to a receiver module at given permission timings, a radio transmission module that wirelessly transmits data when the transmission is permitted, and a power source that supplies power to each module. The signal processor module has a microcomputer and an interval timer that outputs a first timing signal when a count value corresponds to a set value. The microcomputer is activated by the first timing signal and changes the set value in a compare register according to a vehicle operation state.

Abstract: A system for detecting electrolysis in an automobile system includes a probe, a microcontroller electrically coupled to the probe, a power supply configured to supply power to the microcontroller, a ground lead, and an optical indicator operationally coupled to the microcontroller. According to one embodiment, the microcontroller is configured to read a voltage across the probe and the ground lead when the probe is inserted into a coolant fluid and the ground is coupled to a ground source, analyze the voltage, and illuminate the optical indicator in response to the voltage analysis.

Abstract: A temperature warning system for a heavy-duty vehicle, having at least one axle formed with an inner diameter. The axle includes a pair of spindle ends, and a wheel end assembly rotatably mounted on each spindle end. A thermal switch is disposed in the inner diameter of at least one of the axle spindle ends. The switch is electrically connected to a control module to form a closed electrical circuit, and the control module is electrically connected to an indicator device. When the temperature of the switch reaches a predetermined minimum temperature, such as from undesirable increased temperature in the axle spindle end and/or the wheel end assembly, the switch opens, breaking the closed electrical circuit, and causing the control module to activate the indicator device. The indicator device is viewable by the vehicle operator during its operation, thus warning the operator of the undesirable high temperature condition.

Abstract: A controlling device includes a range switch mechanism, range switch operating means, operation frequency monitoring means, and heat generation limit controlling means. The range switch mechanism is adapted to change a shift range using a motor. Through the range switch operating means, an occupant inputs a required shift range. The motor is controlled in accordance with the required shift range such that the shift range is changed into the required shift range. The operation frequency monitoring means monitors an operation frequency of the range switch operating means. The heat generation limit controlling means switches a control of the motor to a heat generation limit control when the operation frequency of the range switch operating means exceeds a predetermined frequency.

Abstract: Each sensor is provided with an emitter and the vehicle is provided with a corresponding receiver adapted to receive signals emitted by each sensor. The receiver is provided with at least one antenna disposed such that it is not located substantially equidistantly from the sensors, the antennas being located on a same side of the vehicle. The location of the sensors is carried out by analyzing the power of the field received by the receiver of each antenna for each sensor, the field power received by one antenna being the greater, the nearer to the antenna is the sensor that emitted the corresponding signal.

Abstract: A system (10) and method manages battery (13) power in a wheel module (11) for indicating when air pressure in a tire falls below a recommended value. Tire air pressure is sensed with a pressure sensor (16). Tire air temperature is sensed with a temperature sensor (18). A determination is made whether the air pressure is increasing or decreasing with respect to time. Based upon whether a ratio of the air pressure and the air temperature is increasing, decreasing or remaining constant with respect to time, tire motion is inferred without directly sensing acceleration or movement of the tire. Power management circuitry (14) controls battery power to enable sensing of air pressure and air temperature at measurement intervals that are longer in time when the tire is not in motion.

Abstract: A magnetic temperature sensing device for rotatably moving parts, of the type including at least a magnetic field source element associated to the rotatably moving part and a magnetic field sensing element associated with a fixed part to measure parameters of a magnetic field determined by the magnetic field source element, the parameters of the magnetic field being a function of the temperature of the rotatably moving part. The magnetic field source element permits rotation along at least an axis the direction of the magnetic field as a function of the temperature of the rotatably moving part.

Abstract: The vehicle-mounted display unit includes a display having a meter area and an auxiliary indication area. The meter area indicates a dial image for showing measured values of an operational condition of a motor vehicle. The auxiliary indication area indicates information other than the measured values. The display unit has a control device for controlling contents indicated on the display. The control device indicates a normal length pointer extended in the auxiliary indication area at a normal indication state, while the control device indicates a shorter length pointer in the auxiliary indication area when the other information is indicated.

Abstract: An interrogator is disposed in a main body of a vehicle for transmitting interrogating signals. A responder is mounted to each tire of the vehicle for returning tire information such as air pressure to the interrogator in response to the interrogating signals. The responder is provided with at least one sensor for detecting tire information and a sensor specifying means for specifying properties of the sensor. The interrogator is provided with a control means for processing tire information, and correction tables for correcting properties of a sensor specified by the sensor specifying means. The control means corrects the tire information by the correction tables and then outputs data related to the tire information.

Abstract: A temperature tracking and monitoring system used for commodities transportation comprises a deliver unit, a control computer and a monitor and control unit. The deliver unit comprises a transportation means, at least a glove compartment, a RFID tag and a RFID reader. The glove compartment is disposed in the transportation device the RFID tag is disposed in the glove compartment and has provision for transmitting an identification code. The control computer is adapted to communicate with the RFID reader to receive a temperature signal and the identification code. The control computer transmits a positioning request signal, receives real-time position data, transforms the real-time position data into a position signal and transmitting the position signal, the temperature signal and the identification code in a specific manner. The monitor and control portion comprises a positioning device and a logistics center.

Abstract: A transmitter in an apparatus for monitoring a condition of a tire attached to a wheel of a vehicle is fixed to the wheel such that the transmitter faces an outer circumferential surface of a wheel rim. The transmitter includes a circuit portion that detects the condition of the tire. The transmitter includes a casing that accommodates the circuit portion, and a leg that extends from the casing toward the outer circumferential surface of the wheel rim. The extended amount of the leg is adjustable such that the leg contacts the outer circumferential surface of the wheel rim when the transmitter is fixed to the wheel. Therefore, the transmitter is mounted to the wheel such that legs of the casing abut against the wheel rim regardless of the size of the wheel.

Abstract: A vehicular remote control system has a mobile unit, a vehicle unit for establishing bidirectional wireless communication with the mobile unit, wherein the vehicle unit is able to transmit a wireless signal to the mobile unit through transmission antennas provided at a plurality of positions of a vehicle, and operational intention detector, provided at the plurality of positions of the vehicle corresponding to the transmission antennas, for detecting operational intention of a user approaching the positions. When a user's operational intention is detected, a predetermined request signal is transmitted from the vehicle unit to the mobile unit through a first transmission antenna, and the vehicle unit transmits an interrupt signal for preventing reception of the request signal, through a second transmission antenna.

Abstract: A method and apparatus is described for enabling a single sensor to indicate a greater quantity of information about a sensed event, or the occurrence of many different types of events. A sensor system employs a number of individual sensors with single-use indication means (such as an explosive charge). Each individual sensor is equipped with a chronometer. The sensors are programmed to transmit information through their single-use indication means at specific times with each specific time being indicative of a particular type of event or of specific information about an event. A central monitor chronologically records all sensor indications and compares indication times to a schedule of time keyed information to determine the nature of each sensor indication.

Abstract: A detection/communication apparatus to be installed on a vehicle having a plurality of tires. The apparatus includes: (a) tire state detectors which are provided on the respective tires and each of which detects a state of a corresponding one of the tires; (b) local transceivers which are provided on the respective tires and which transmit tire data sets relating to the respective tires; (c) a central receiver which is provided on a vehicle body and which receives the tire data sets transmitted by the local transceivers; (d) a particular-signal transmitter which is provided on the vehicle body and which transmits a particular signal; and (e) data-transmission modifiers which are provided on the respective tires. Each of the data-transmission modifiers is operable depending upon a state of reception of the particular signal by a corresponding one of the local transceivers, to modify transmission of a corresponding one of the tire data sets by the corresponding one of the local transceivers.

Abstract: A multiple heat sensor alarm system for use in a vehicle to indicate that the interior temperature is above a preset limit has a control head with a microprocessor. Heat sensors or thermometers are placed at different points in the vehicle and connected to the microprocessor. The processor averages all sensor inputs and compares the average to the preset alarm temperature limit. When the limit is exceeded the microprocessor issues an alarm command. The system is connected to the vehicle components and the alarm command operates the horn, lights, windows, doors, or engine. The system may correspond with a portable beeper/pager. The microprocessor has a time delay mode on initial start-up. The system also monitors the battery power of the vehicle and indicates a low power situation.

Abstract: System state indicator in particular for a vehicle dashboard, the system having a given use potential and comprising evaluation means such that, on the basis of measurements related to the conditions of use of the vehicle and/or the physical characteristics of the system and/or the vehicle and/or the vehicle environment conditions, the evaluation means calculate at a time t parameters characteristic of the state of the system, characterized in that the state indicator simultaneously displays at time t at least three different parameters characteristic of the state of the system and its range.

Abstract: A tire monitoring system providing tire status and notifying or warning the vehicle operator of early detection of imminent tire failure and performance degradation; thus improving safety by preventing blowouts from occurring, lengthening tire life by encouraging preventive maintenance, and improving fuel mileage by encouraging the operator to fill the tire to its proper pressure or repair it. The system monitors temperature of the rim of the wheel to which the tire is attached, such temperature being transmitted to the vehicle operator or other interested parties via means such as radio frequency.

Abstract: Tires of wheels of a vehicle incorporate detectors that detect the pneumatic pressures and transmit them wirelessly to a plurality of receivers installed on the vehicle. A monitoring device monitors the pneumatic pressures in the tires based on the tire data obtained by the receivers. The receivers and the monitoring devices are connected together through a single communication line, and the monitoring device obtains tire data from the receivers by polling. For each receiver, a receiver ID necessary for the communication with the monitoring device of the vehicle-side is set through a connector that connects the single communication line and the power source line to the receiver.

Abstract: Early stage detection of engine liquid cooling problems is provided with temperature, pressure and other sensors and associated logic circuits configured for detecting alarm conditions including below normal static coolant pressure coupled with an elevated coolant temperature, above normal static coolant pressure, below normal coolant pump pressure condition, coolant voids due to coolant loss or boiling, and external steam or liquid leakage from the cooling system. A gauge displays the difference between coolant pump output pressure and static coolant pressure.

Abstract: A catalyst coating 5 for decomposing ozone in the air is applied to an outer surface of cooling pipes 3 and radiating fins 4 of a radiator 2. A peel sensor 2 is provided on the catalyst coating 5 of the radiator 2 to detect a loss (remaining amount) of the catalyst coating 5. The position of detection of the peel sensor 2 is determined according to a temperature characteristic of the radiator 2, and a flow rate of the air passing through the radiator 2. The position of detection of the peel sensor 2 can be determined easily and appropriately, such that loss and deterioration of the catalyst coating 5 can be detected with high precision.

Abstract: A monitoring system, particularly suitable for monitoring conditions (e.g. pressure or temperature) of a vehicle tire comprises a passive sensor (102, 104), an antenna (106) associated with said passive sensor, and switching means (108) for controlling the connection between the passive sensor and the antenna such that, in a first state of said switching means, said antenna is prevented from transmitting a signal generated by the passive sensor, and, in a second state of said switching means, said antenna is permitted to transmit a signal generated by the passive sensor. The switching means is operated remotely by means of a control signal. The control signal may be derived from the sum or difference of RF signals (F1 and F2) applied to a filter (112) In alternative embodiments the control signal is the modulating frequency of an AM or FM modulated radio signal or a radio signal carrying a digital code.

Abstract: An engine temperature monitoring device for alerting a vehicle operator that an engine is overheated includes a heat sensor adapted for detecting ambient temperature levels. A processor adapted for monitoring the temperature levels is operational coupled to the heat sensor. A speaker for producing an audible sound is operationally coupled to the processor. The speaker is turned on when the heat sensor detects a temperature of the engine which is greater than an acceptable tolerance. A power supply is operationally coupled to the processor. The heat sensor is secured to the engine such that the heat sensor may detect the temperature of the engine.

Abstract: A child car seat with a built-in cushion switch that closes when the seat is occupied. Also, push type switches are added to at least one of the vehicle's side passenger doors with signals being routed to a micro-controller unit, which determines when the car seat is occupied AND when one of the doors is open and enables the vehicle's internal beeper alarm, thereby reminding any occupants exiting the vehicle that a child is strapped in the back seat. Additionally, an inside temperature sensor is coupled to the micro-controller unit, which sets off a loud external alarm such as the vehicle's security alarm, when the temperature inside the vehicle goes above or below a safe preprogrammed environmental range. This is an additional safety feature that will get the attention of people outside the vehicle, indicating that a child is trapped in a dangerous environment inside the vehicle and needs help.

Abstract: A vehicle includes at least one wheel and an associated brake. Especially if the vehicle is traveling down an incline, the brake may overheat from prolonged use. The present invention provides an operator warning device which alerts the operator to a possible or actual brake overheat condition, based on any number of chosen non-temperature vehicle conditions. These conditions may include incline, machine speed, brake application pressure, and brake application duration.

Abstract: A thermal monitoring system for use with a tire is provided. The system includes one or more thermal sensors that are carried by a vehicle. One of the thermal sensors may produce a first sensor output signal that is representative of the temperature of a first location on the tire. Additionally, a second sensor output signal may be produced that is representative of the temperature of a second location on the tire. A signal processing device is included that receives the first and second sensor output signals. The signal processing device produces a processing device output signal that is representative of a potential damage condition of the tire. This signal is produced in response to a particular temperature difference between the first and second locations as indicated by the first and second sensor output signals. An indication device receives the processing device signal and indicates to a user of the vehicle that the tire is experiencing a potential damage condition.

Abstract: The present invention provides a method, a computer usable medium including a program, and a system for monitoring inflation in a plurality of vehicle tires. The method and computer usable medium include the steps of determining a direct pressure in at least one primary tire and determining a rolling radius for the primary tire and at least one secondary tire. A pressure difference is determined based on the determined rolling radius for the primary and secondary tires. The determined pressure difference is adjusted based on the determined direct pressure of the primary tire. The determined pressure difference is compared to at least one threshold value. The system includes means for achieving the method steps of the invention.

Abstract: A tire pressure control arrangement for a motor vehicle monitors the air pressure of at least one pneumatic tire and a signal is outputted from the arrangement when, in at least one tire of the motor vehicle, the air pressure drops below a lower threshold value or exceeds an upper threshold value. The lower and/or upper threshold value(s) are set in dependence upon the laden state of the motor vehicle. The laden state is determined with the aid of an air suspension system and the setting takes place automatically with the aid of the determined laden state.

Abstract: A machine to turn on the occupancy sensor(s) of a motor vehicle using a temperature sensing element. The temperature element senses a dangerously high temperature in the passenger compartment of a motor vehicle and energizes the occupancy sensors. The occupancy sensors energize for a time period sufficient to determine the presence or absence of an occupant. If no occupant is detected, the occupancy sensors de-energize after a set period of time. If an occupant is detected, an audible alarm is enabled to draw attention to the motor vehicle. Once the alarm is active, a key must be used to reset it. If no occupant is detected each operation of a door switch will cause an additional sensing provided the temperature remains dangerously high. This logic is only energized or enabled when a passenger compartment is dangerously high.

Abstract: A transmitter for a tire condition monitoring apparatus is located in a tire of a vehicle and transmits data indicating the tire condition using a carrier wave. The transmitter includes an oscillating circuit and a controller. The oscillating circuit generates a carrier wave frequency and has a predetermined characteristic carrier wave frequency. The controller corrects the generated carrier wave frequency in accordance with the difference between the characteristic carrier wave frequency and a predetermined reference carrier wave frequency.

Abstract: Safety systems for vehicles, primarily passenger vehicles, comprising automated systems and methods for preventing entrapment of children, disabled, aged or infirm persons, or pets from being trapped in closed vehicles left in the sun, so that they will not suffocate from the heat. The invention is characterized by use of one or more systems to sense the occupancy state and temperature inside the vehicle passenger or load space, and provide one or more outputs which can selectively be employed to provide interior and exterior warning of a trapped passenger in a dangerously hot car to permit rescue, and/or to activate vehicle electro-mechanical systems to relieve the heat, such as rolling down windows, unlatching seat belts, unlocking doors, starting the car and/or fans or air conditioning systems and the like.

Abstract: In one embodiment of the present invention, an apparatus for detecting a hot rail car surface comprises: an infrared sensor for acquiring an infrared signal from a rail car surface of a rail car and transducing the infrared signal into an electrical signal; a rank filter for filtering the electrical signal to produce a filtered array; a first peak detector for detecting a maximum filtered value of the filtered array; and a first comparator for comparing the maximum filtered value to a detection threshold to produce a filtered alarm signal.

Abstract: A method for monitoring thermal overload of an electric load element in a motor vehicle containing other electric consumers, which can be switched into a stand-by phase is disclosed. The load element is monitored by a control device using a calculated load temperature parameter. During a first operational phase, a power loss of the load element or a quantity that is essentially proportional thereto is evaluated for calculating the load temperature parameter. During one or more stand-by phases, the control device is switched with essentially no current between the first operational phase and a second operational phase. After the control device is switched on in the second operational phase, at least one quantity, which is characteristic for the moment of switching on, is evaluated for calculating the existing load temperature parameter.

Abstract: A method of signaling for a change of an air filter of a vehicle air conditioning system is disclosed. The present invention uses a sensor installed in a conventional air conditioner and the appropriate time for changing the air filter is determined by checking compressor operation when a degree of airflow is decreased during air conditioner operation.

Abstract: The present invention provides a method of inferring the engine coolant temperature in cylinder head temperature sensor equipped vehicles including the steps of measuring the cylinder head temperature, calculating the engine coolant temperature from the measured cylinder head temperature as a function of at least one vehicle operational state, generating a signal for the calculated engine coolant temperature, and sending the generated signal to a display.