Provided is a load drive device capable of diagnosing a failure of an output terminal of the load drive device before a charging voltage stabilizes in a configuration in which a capacitor is connected to an output terminal of the load drive device that drives an inductive load. In the load drive device according to the present invention, a capacitor is connected between a load terminal and a ground terminal, and the presence or absence of a failure of the load terminal is diagnosed on the basis of a current flowing between an internal power supply included in a diagnosis circuit and the load terminal.

With a simple configuration, responsiveness between an electronic control unit and a load drive circuit is monitored without deteriorating characteristics of the load drive circuit. The load drive circuit according to the present invention diagnoses an abnormality in responsiveness of a switch element that drives a load based on a drive command of the switch element and a signal at an output terminal of the switch element.

A large current flowing when energization by normal load drive control is performed at the time of a load short-circuit is prevented. A load drive device 100 includes drive switches 61 and 62 that turn on or off the current supplied from a power source to a load 70, a switch drive circuit 20 that transmits a drive signal to the drive switches 61 and 62 based on a control command from an arithmetic device 10, and a constant current source 40 that supplies the current to the load 70 without passing through the drive switches 61 and 62. Then, the switch drive circuit 20 performs control so as not to turn on either the drive switches 61 or 62 when the voltage between both ends of the load 70 becomes equal to or less than the determination value in a state where the drive switches 61 and 62 are turned off and in a state where the current is supplied from the constant current source 40 to the load 70.

To provide a sensor control device capable of identifying a short circuit terminal with a simple configuration and whose identification operation is not easily affected by environmental conditions around the sensor. The sensor control device includes a short circuit detection unit that detects a short circuit of a sensor having a plurality of terminals, a resistance value control unit that increases a resistance value of an element between the terminals when the short circuit of the sensor is detected by the short circuit detection unit, and a short circuit terminal identification unit that identifies at which of the plurality of terminals a short circuit occurs when the resistance value control unit increases the resistance value of the element between the terminals to a set value or greater.

An EHC line leakage diagnosis method can operate a heater of an oxygen detector when satisfying one or more conditions of an engine off time, a coolant temperature, and an outside air temperature by a diagnosis controller upon the key-on of the non-operation of an engine, and then, determine the normality or abnormality of a temperature drop using a change in a temperature value of a signal value and the temperature value detected by the oxygen detector after an air pump is driven, and then confirm the leakage of an exhaust line and a line on the rear end portion of an EHC valve of an air line using the number of times of the occurrence of the abnormality of the temperature drop, and can perform the failure diagnosis without generating the exhaust gas by not operating an engine.

The invention relates to a method for determining a characteristic value of a magnetic switch valve. The magnetic switch valve can be switched from a closed switch state into an open switch state, via the movement of a rotor by means of a switching magnet applied with current against a conservative restoring force. According to the invention, during the switching of the switch valve from the open state into the closed state, the time course of the current flowing through the switching magnet and/or of the voltage at the switching magnet is measured. The characteristic value to be measured is evaluated from this time course. It was recognised that every movement of the rotor against the switching magnet induced a voltage in same. Now the voltage at the switching magnet is regulated at a constant value, for one, the voltage induced by the movement can be observed as a control deviation in the short term. For another, the induced voltage causes a current flow through the switching magnets. Based on this, the kinematics of the rotor can be deduced. Given that the switching magnet has an ohmic resistance, energy is also dissipated via the current flow. This energy is the key to determining the switching path covered by the rotor when switching between the closed and the open state. The invention also relates to a measuring device that is particularly suitable for the method.

A system for controlling the operation of one or more fuel injectors includes a microcontroller, a pre-driver unit, and a power unit. The system is connectable to an electrically actuated fuel injector via at least two wires from the power unit, wherein the pre-driver unit is located between the microcontroller and the power stage, and wherein the microcontroller unit is adapted to send data to the pre-driver unit. The pre-driver unit is adapted to receive the data and control the power stage dependent on the data such that the power stage is adapted to output a corresponding signal along the wires to the fuel injector. The data includes both injector activation pulse data and other auxiliary data for the injectors.

An abnormality determination device includes an injection instructor that realizes a rich state of an air-fuel ratio in an exhaust gas by sending an instruction of (i) stopping an application of bias to a plus terminal and (ii) adjusting a fuel injection amount from an injector, and an abnormality determiner that distinctively determines abnormality of, i.e., in terms of which one of, the plus terminal or a minus terminal having a sky failure or a ground failure by detecting an electromotive force of an air-fuel ratio sensor when the air-fuel ratio in the exhaust gas is in the rich state according to the instruction of the injection instructor.

Provided is a load drive device capable of diagnosing a failure of an output terminal of the load drive device before a charging voltage stabilizes in a configuration in which a capacitor is connected to an output terminal of the load drive device that drives an inductive load. In the load drive device according to the present invention, a capacitor is connected between a load terminal and a ground terminal, and the presence or absence of a failure of the load terminal is diagnosed on the basis of a current flowing between an internal power supply included in a diagnosis circuit and the load terminal.

To provide a sensor control device capable of identifying a short circuit terminal with a simple configuration and whose identification operation is not easily affected by environmental conditions around the sensor. The sensor control device includes a short circuit detection unit that detects a short circuit of a sensor having a plurality of terminals, a resistance value control unit that increases a resistance value of an element between the terminals when the short circuit of the sensor is detected by the short circuit detection unit, and a short circuit terminal identification unit that identifies at which of the plurality of terminals a short circuit occurs when the resistance value control unit increases the resistance value of the element between the terminals to a set value or greater.