Abstract: A microcomputer of a driving force distribution control device detects a maximum current value among values of an upper current acquired during a predetermined period, and determines that an overcurrent abnormality has occurred in the driving force distribution control device when the maximum current value is equal to or larger than an abnormal current threshold value and a time, for which the maximum current value is equal to or larger than the abnormal current threshold value, is equal to or larger than an abnormality detection time. Then, the microcomputer performs off control to turn off a relay, and notifies a driver of occurrence of the overcurrent abnormality using a notification unit.

Abstract: A solenoid control device executes feedback control such that a drive current for a solenoid follows a target current, by driving, through PWM, a MOSFET provided on a power supply line to the solenoid. An overcurrent detection circuit that outputs an overcurrent detection signal when the drive current for the solenoid reaches an overcurrent determination current value is provided, and it is determined whether an overcurrent is generated. Whether a short-circuit occurs between both terminals of the solenoid is determined by monitoring whether the overcurrent detection circuit is repeating an output of the overcurrent detection signal and a stop of the output of the overcurrent detection signal.

Abstract: A microcomputer of a driving force distribution control device detects a maximum current value among values of an upper current acquired during a predetermined period, and determines that an overcurrent abnormality has occurred in the driving force distribution control device when the maximum current value is equal to or larger than an abnormal current threshold value and a time, for which the maximum current value is equal to or larger than the abnormal current threshold value, is equal to or larger than an abnormality detection time. Then, the microcomputer performs off control to turn off a relay, and notifies a driver of occurrence of the overcurrent abnormality using a notification unit.

Abstract: A driving force distribution control device controls an inductive load circuit to adjust a ratio of driving forces transmitted from a driving source to a plurality of wheels via a driving force transmitting system. The driving force distribution control device counts a number of tests performed by applying a test current to the inductive load circuit; determines that a disconnecting abnormality occurs in an electric load including the inductive load circuit if a difference between a value of the test current and a value of current flowing in the inductive load circuit is greater than a current difference threshold value; and determines that the disconnecting abnormality is definitive if the number of tests is equal to a threshold value or more, and also if the number of determinations of the disconnecting abnormality is equal to a predetermined threshold value or more.

Abstract: A solenoid control device executes feedback control such that a drive current for a solenoid follows a target current, by driving, through PWM, a MOSFET provided on a power supply line to the solenoid. An overcurrent detection circuit that outputs an overcurrent detection signal when the drive current for the solenoid reaches an overcurrent determination current value is provided, and it is determined whether an overcurrent is generated. Whether a short-circuit occurs between both terminals of the solenoid is determined by monitoring whether the overcurrent detection circuit is repeating an output of the overcurrent detection signal and a stop of the output of the overcurrent detection signal.

Abstract: An offset value setting processing, in which whether or not all wheel velocities of front wheels and rear wheels are 0 km/h is determined and whether or not a pressing amount of an accelerator pedal is 0% is determined. If it is determined that the vehicle velocity is 0 km/h and that the pressing amount of the accelerator pedal is 0%, a current detection signal voltage at that time is set to an offset voltage. Thus, the offset voltage value is reset and set again if such a condition is established. Consequently, the offset voltage value including the amount of an error due to a temperature drift is set up, thereby preventing drop in control accuracy due to that error.

Abstract: A drive power transmission control device is provided with an electromagnetic drive power transmission device and an ECU for controlling the application of electric current to an electromagnetic coil of the drive power transmission device. The ECU is bodily provided on a casing of the electromagnetic type drive power transmission device through at least one support member 50. The electronic control device is fixedly supported on an outer wall of the casing with a space between the electronic control device and the casing, such that cooling air can flow between the outer wall of the casing and the electronic control device.

Abstract: An abnormality detection apparatus, which reduces erroneous detection of an open abnormality of a relay, includes a microcomputer that activates the relay and determines whether the output voltage of the relay is less than a threshold value. When the output voltage is less than the threshold value, the microcomputer repeats the activation of the relay and the determination. The detection unit detects the occurrence of an open abnormality when the repetition number exceeds two.

Abstract: A hunting detecting device used for an electrical load detecting device sets a current command value for an electrical load. Based on a deviation between a current that actually flows through the electrical load and the current command value, the hunting detecting device performs at least proportional control in a group including proportional control, integral control, and differential control. The hunting detecting device sends a current generated based on the performed control to the electrical load. A current determining device determines whether there is a current through the electrical load. When the current determining device determines that there is a current through the electrical load, a hunting detector detects a number of times of hunting within a predetermined period.

Abstract: An offset value setting processing, whether or not all wheel velocities of front wheels and rear wheels are 0 km/h is determined and whether or not a pressing amount of an accelerator pedal is 0% is determined. If it is determined that the vehicle velocity is 0 km/h and that the pressing amount of the accelerator pedal is 0%, a current detection signal voltage at that time is set to an offset voltage. Thus, the offset voltage value is reset and set again if such a condition is established. Consequently, the offset voltage value including the amount of an error due to a temperature drift is set up, thereby preventing drop in control accuracy due to that error.

Abstract: A drive power transmission control device in a first embodiment is provided with an electromagnetic type drive power transmission device and an electronic control device (ECU) for controlling the application of electric current to an electromagnetic coil of the electromagnetic type drive power transmission device. The ECU is bodily provided on a casing of the electromagnetic type drive power transmission device through at least one support member 50. Thus, nonuniformity or deflection in mechanical quality of the electromagnetic type drive power transmission device and nonuniformity or deflection in electrical quality of the electronic control device can be adjusted as a whole, and the drive power transmission control device is lightened in weight. A drive power transmission control device in a second embodiment is provided with an electronic control device for controlling drive power transmitted by a drive power transmission device from a drive power source to plural wheel.

Abstract: A four-wheel drive vehicle provides a torque distribution clutch mechanism which directly transmits the driving force generated from the engine to one of two front wheels or two rear wheels, and which transmits it to the other wheels therethrough in order to control the engaging force in accordance with a traveling status of the four-wheel drive vehicle. The vehicle further comprises a tight corner judging structure, a normal mode setting structure, a low friction road judging structure and a tight mode setting structure. The tight corner judging structure judges whether the vehicle travels at a large turning angle or not, and the normal mode setting structure sets a normal mode to control the engaging force when it is judged by the tight corner judging structure that the vehicle does not travel at the large turning angle.

Abstract: The four-wheel-drive vehicle has a torque transmission device configured to distribute torque transmitted from an engine to a first set of wheels to a second set of wheels. Throttle-opening of the engine is detected. A first torque command which depends on the throttle-opening is obtained. A rotational speed difference between the first set of wheels and the second set of wheels is detected. A second torque command which depends on the rotational speed difference is obtained. The torque transmission device is controlled based on the first and the second torque command so as to transmit the driving force to the second set of wheels according to the throttle-opening and the rotational speed difference. Then, a signal that corresponds to the throttle-opening is monitored. When the signal is judged being abnormal, the first torque command is ignored so that the torque transmission device is controlled based on the second torque command.

Abstract: A torque distribution control device for a four-wheel drive vehicle has a torque distribution device for distributing the drive power transmitted from an engine to either of the front wheels or the rear wheels as prime drive wheels, to other wheels as sub-drive wheels. The control device judges whether or not an abnormality is involved in wheel speed signals which are input from wheel speed sensors associated respectively with the front and rear wheels. A normal-state method of calculating a command torque which is applied to the torque distribution device to vary the drive power transmitted to the sub-drive wheels, is then altered to an abnormal-state method of calculating the command torque based on data which does not include one wheel speed signal involving the abnormality when the same occurs with one of the wheel speed signals, whereby the vehicle is enabled to continue the four-wheel drive even when the abnormality occurs.

Abstract: A four-wheel drive vehicle is provided with a drive power transmission device for controlling the connection degree of a front wheel axle driven by an engine with a rear wheel axle. A drive power distribution control device is responsive to a vehicle speed, a rotational difference between front wheels driven by the front wheel axle and rear wheels driven by the rear wheel axle, a throttle opening degree signal and the like and controls the drive power transmission device. The drive power distribution control device judges whether the vehicle is beginning to start or not and at the starting of the vehicle, controls the transmission rate of the drive power transmission device in dependence on the state or manner in which the vehicle is beginning to start.

Abstract: A calculator for calculating an opened amount of a throttle valve with high accuracy regardless of voltage fluctuation and noise. The calculator includes a valve sensor for detecting the opened amount of the throttle valve to generate a detection voltage. A memory stores an initial zero point detection value. A calculation circuit obtains the difference between the detection voltage and the initial zero point detection value and calculates the opened amount of the throttle valve with the difference. When a plurality of detection voltages that are less than the initial zero point detection value are generated, the calculation circuit calculates a new zero point detection value that is greater than a smallest one of the plurality of detection voltages by a predetermined value and updates the initial zero point detection value with the new zero point detection value.

Abstract: A hunting detecting device used for an electrical load detecting device sets a current command value for an electrical load. Based on a deviation between a current that actually flows through the electrical load and the current command value, the hunting detecting device performs at least proportional control in a group including proportional control, integral control, and differential control. The hunting detecting device sends a current generated based on the performed control to the electrical load. A current determining device determines whether there is a current through the electrical load. When the current determining device determines that there is a current through the electrical load, a hunting detector detects a number of times of hunting within a predetermined period.

Abstract: A four-wheel drive vehicle is provided with a drive power transmission device for controlling the connection degree of a front wheel axle driven by an engine with a rear wheel axle. A drive power distribution control device is responsive to a vehicle speed, a rotational difference between front wheels driven by the front wheel axle and rear wheels driven by the rear wheel axle, a throttle opening degree signal and the like and controls the drive power transmission device. The drive power distribution control device includes a vehicle starting judgment means for judging whether the vehicle is beginning to start or not and at the starting of the vehicle, controls the transmission rate of the drive power transmission device in dependence on the state or manner in which the vehicle is beginning to start.

Abstract: The four-wheel-drive vehicle has a torque transmission device configured to distribute torque transmitted from an engine to a first set of wheels to a second set of wheels. Throttle-opening of the engine is detected. A first torque command which depends on the throttle-opening is obtained. A rotational speed difference between the first set of wheels and the second set of wheels is detected. A second torque command which depends on the rotational speed difference is obtained. The torque transmission device is controlled based on the first and the second torque command so as to transmit the driving force to the second set of wheels according to the throttle-opening and the rotational speed difference. Then, a signal that corresponds to the throttle-opening is monitored. When the signal is judged being abnormal, the first torque command is ignored so that the torque transmission device is controlled based on the second torque command.

Abstract: A four-wheel drive vehicle provides a torque distribution clutch mechanism which directly transmits the driving force generated from the engine to one of tow front wheels or two rear wheels, and which transmits it to the other wheels therethrough in order to control the engaging force in accordance with a traveling status of the four-wheel drive vehicle. The vehicle further comprises a tight corner judging means, a normal mode setting means, a low friction road judging means and a tight mode setting means. The tight corner judging means judges whether the vehicle travels at a large turning angle or not, and the normal mode setting means sets a normal mode to control the engaging force when it is judged by the tight corner judging means that the vehicle does not travel at the large turning angle.