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.

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 method and a device for performing diagnostics on an exhaust gas sensor includes a series circuit of a Nernst cell and a first other cell. The exhaust gas sensor has a first, a second, and a third connection where a voltage drop can be measured between the first connection and the second connection by the Nernst cell and a voltage drop between the second connection and the third connection can be measured by the first other cell. The diagnostic method has steps for feeding a direct or alternating current into the first, second, and third connections; for directly or indirectly sensing an electrical voltage potential at at least one of the first, second, and third connections; and for evaluating the voltage potential sensed to diagnose a short circuit or an open circuit in the Nernst cell and/or in the first other cell.

A continuously variable valve duration (CVVD) system includes a controller configured to determine whether a learning value existing in the CVVD system is required to be verified during one of a hardware abnormality, a learning value abnormality, and a motor voltage abnormality. In particular, the controller performs a learning value verification control using a rotation detection value and switches from a learning value verification control to a re-learning control when re-learning is required.

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.

A continuously variable valve duration (CVVD) system includes a controller configured to determine whether a learning value existing in the CVVD system is required to be verified during one of a hardware abnormality, a learning value abnormality, and a motor voltage abnormality. In particular, the controller performs a learning value verification control using a rotation detection value and switches from a learning value verification control to a re-learning control when re-learning is required.

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.

Appropriate detection of an abnormality of voltage information, which is a basis for correcting a fuel injection amount, becomes possible. For this reason, a fuel injection control device 127, which has a drive IC 208 controlling a fuel injection drive unit 207a to supply a high voltage to a solenoid 405 so as to open a fuel injection valve 105 and controlling the fuel injection drive unit 207a to supply a low voltage to the solenoid 405 so as to hold a valve-open state of the fuel injection valve 105, includes: a drive voltage input unit 211 that measures and outputs voltage information based on an upstream voltage of the solenoid 405 of the fuel injection valve 105 and a downstream voltage of the solenoid 405; a fuel injection amount correction unit 213 that corrects a fuel injection amount of the fuel injection valve 105 based on the voltage information output from the drive voltage input unit 211; and a voltage input function abnormality detection unit 212 that detects whether an output of the drive voltage input unit 211 is abnormal based on the voltage information output from the drive voltage input unit 211.

A method for verifying a CVVD location learning result may include performing a learning value verification control by confirming a position of a control shaft connected to a motor with a signal value of an auxiliary cam sensor for a rotation of a camshaft if a controller determines that a learning value acquired in a short duration and a long duration of a CVVD system is desired to be verified.

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.