An electromagnetic valve driving device which drives a fuel injection valve having a solenoid coil, includes: a regenerative switching element disposed between a first end portion of the solenoid coil and the ground; and a control unit configured to control the regenerative switching element to be in an ON state or an OFF state, wherein the control unit includes: a voltage detection unit configured to detect a voltage of the first end portion of the solenoid coil; and an abnormality detection unit configured to detect an abnormality of the regenerative switching element on the basis of the voltage detected by the voltage detection unit.

Provided is an electronic control unit capable of performing a high-accurate failure diagnosis in a short time as an electronic control unit having a failure diagnosis function. A load drive circuit that drives a load, a control circuit that controls the load drive circuit, and a diagnosis circuit that diagnoses an output state of the load drive circuit and outputs a diagnostic result to the control circuit are provided. The diagnosis circuit outputs a diagnosis completion flag indicating whether or not there is a diagnosis opportunity to the control circuit.

Provided is an injector control unit capable of preventing unintended fuel injection other than an engine drive period. The injector control unit includes a cutoff mechanism for cutting off current supply to the injector from at least the ignition OFF to the next ignition ON.

Various embodiments include a method for diagnosis of a high-pressure sensor of a motor vehicle comprising: measuring a pressure with the high-pressure sensor; feeding the measured pressure to a control unit; evaluating the measured pressure with the control unit and determining a control signal for an amount of fuel to be injected; checking whether a first difference between two successive values of the pressure measurement signal is greater than a calculated maximum difference value; checking whether a second difference between a minimum pressure measurement signal measured within a time segment and a maximum pressure measurement signal measured within the time segment is less than an expected change in the pressure measurement signal; and checking whether a measured pressure gradient is smaller than an expected pressure gradient.

An internal combustion engine control device that can ensure diagnosis of whether a fuel injection cut function normally works and that further permits startup of an internal combustion engine in a case in which the fuel injection cut function normally works is provided. To attain the internal combustion engine control system, the startup of the internal combustion engine is prohibited when carrying of a diagnostic monitoring current based on a diagnostic drive signal related to each of fuel injection valves to each of fuel injection valves in a case of transmitting a drive prohibition signal related to each of fuel injection valves to a fuel injection valve drive circuit before the startup of the internal combustion engine and transmitting the diagnostic drive signal related to each of fuel injection valves to the fuel injection valve drive circuit. By transmitting the diagnostic drive signal related to each of the fuel injection valves to the fuel injection valve drive circuit and monitoring whether the diagnostic monitoring current based on the diagnostic drive signal is carried to each of fuel injection valves, it is possible to ensure diagnosis of whether the fuel injection cut function normally works.

A fuel injection control device includes an injection valve drive circuit that drives a plurality of injection valves, a booster circuit that generates a boosted voltage supplied to the injection valve drive circuit; and a fuel pump drive circuit that drives a fuel pump for compressing fuel of an internal combustion engine. The fuel pump drive circuit is configured to, when driving the fuel pump, regenerate energy into the booster circuit. The injection valve drive circuit is configured to, during a non-drive period of the injection valves or during a period in which the fuel pump is intermittently driven continuously, perform a non-valve opening energization on at least one of the plurality of injection valves.

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 method of operating an oxygen sensor system is provided where the system includes an oxygen sensor, the oxygen sensor including a pump cell, and wherein the oxygen sensor is connected to associated circuitry such that the associated circuitry controls operation of the pump cell. The pump cell includes a pump line connected to a pump electrode of the pump cell and a return line connected to a return electrode of the pump cell. The method includes, subsequent to a diagnostic process, raising the potential of the pump line for a predetermined period of time by injecting current onto the pump line.

A fuel injection control device includes an injection valve drive circuit that drives a plurality of injection valves, a booster circuit that generates a boosted voltage supplied to the injection valve drive circuit; and a fuel pump drive circuit that drives a fuel pump for compressing fuel of an internal combustion engine. The fuel pump drive circuit is configured to, when driving the fuel pump, regenerate energy into the booster circuit. The injection valve drive circuit is configured to, during a non-drive period of the injection valves or during a period in which the fuel pump is intermittently driven continuously, perform a non-valve opening energization on at least one of the plurality of injection valves.

An internal combustion engine control device that can ensure diagnosis of whether a fuel injection cut function normally works and that further permits startup of an internal combustion engine in a case in which the fuel injection cut function normally works is provided. To attain the internal combustion engine control system, the startup of the internal combustion engine is prohibited when carrying of a diagnostic monitoring current based on a diagnostic drive signal related to each of fuel injection valves to each of fuel injection valves in a case of transmitting a drive prohibition signal related to each of fuel injection valves to a fuel injection valve drive circuit before the startup of the internal combustion engine and transmitting the diagnostic drive signal related to each of fuel injection valves to the fuel injection valve drive circuit. By transmitting the diagnostic drive signal related to each of the fuel injection valves to the fuel injection valve drive circuit and monitoring whether the diagnostic monitoring current based on the diagnostic drive signal is carried to each of fuel injection valves, it is possible to ensure diagnosis of whether the fuel injection cut function normally works.