摘要:
A procedure for checking the functionality of an electric heating device (10) with at least one PTC-element (13, 14) is suggested. The electric heating device (10) is operated at a battery voltage. When controlling the heating device (10) it is impinged with a current and at least one measuring value is detected, which represents the current that flows through the heating device. The measuring value for the current is compared to at least one reference value with a default tolerance width while considering the battery voltage. In the case of a measuring value that deviates from the reference value an error can be assumed.
摘要:
A procedure for checking the functionality of an electric heating device (10) with at least one PTC-element (13, 14) is suggested. The electric heating device (10) is operated at a battery voltage. When controlling the heating device (10) it is impinged with a current and at least one measuring value is detected, which represents the current that flows through the heating device. The measuring value for the current is compared to at least one reference value with a default tolerance width while considering the battery voltage. In the case of a measuring value that deviates from the reference value an error can be assumed.
摘要:
Procedure for controlling a digital tank fuel level sensor in a tank that is subjected to movements is thereby characterized, in that sloshing events are determined and in that the fuel level around the encoder position (205) in the tank is concluded from the number of sloshing events and in that from that the functioning of the tank fuel level sensor can be assumed.
摘要:
A method for operating a metering valve and a device for performing the method, providing for diagnosis of the metering valve which defines a flow rate of a reagent to be introduced into an exhaust gas area of an internal combustion engine. The diagnosis is performed on the basis of an analysis of a measure for the flow rate during a diagnosis time. According to a first embodiment, after a diagnosis start signal has occurred with the metering valve closed, the reagent is brought to a predefined diagnosis starting pressure via a pump; the metering valve is then set at a predefined flow rate and the pressure difference occurring during the diagnosis time is analyzed. According to another embodiment, the amount of reagent delivered by the metering valve during the diagnosis time into a graduated beaker is analyzed.
摘要:
A method for introducing a reagent medium into an exhaust gas conduit of an internal combustion engine (10), and an apparatus for carrying out the method, are proposed. Provision is made for a diagnosis of the pressure sensor (20, 22). In at least one first time interval (t8, t10) in which a steady pressure state is expected, a check is made as to whether the pressure signal (21, 23) at least approximately corresponds to the steady-state pressure (100, 107). In at least one second time interval (t9, t11) in which a pressure change occurs, a check is made as to whether the pressure signal (21, 23) at least approximately corresponds to a predetermined test pressure (104, 108) and/or at least approximately exhibits a predetermined change with respect to the steady-state pressure (100, 107). A fault signal (72) is supplied if at least one of the conditions is not met.
摘要:
A method for operating an exhaust-gas treatment device of an internal combustion engine and a device for carrying out the method, in which a reagent, whose pressure is measured by a reagent pressure sensor, is introduced into the exhaust-gas area upstream from the exhaust-gas treatment device. First the reagent pressure is brought to the exhaust-gas pressure which prevails in the exhaust-gas area upstream from the exhaust-gas treatment device. Then the pressure difference between the reagent pressure and the sum of the exhaust-gas pressure and the ambient air pressure is compared to a predefined pressure difference threshold, and if the pressure difference threshold is exceeded an error signal is supplied. The procedure contributes to an exact metering of the reagent through a diagnosis of the reagent pressure sensor.
摘要:
A method for metering a reagent which an emission control device situated in the exhaust duct of an internal combustion engine requires for removing at least one exhaust gas component from the exhaust gas and a device for executing the method are described. The fluid level of the reagent stored in a reagent tank is measured. The measured change in the fluid level is compared to at least one measure for the change in the fluid level calculated as a function of consumption. An error signal is output when the comparison result exceeds a predefined threshold value. This approach enables reliable information to be provided about the fluid level of the reagent in the reagent tank.
摘要:
A method and a device for controlling an internal combustion engine having a central control unit and a peripheral control unit are described. The central control unit transmits request signals to the peripheral control unit. At least two load circuits receive control signals from the peripheral control unit. The peripheral control unit checks the request signals and/or additional signals for plausibility.
摘要:
The invention relates to a sensor arrangement for determining a tank fill level of a liquid, especially a reducing agent for removing nitrogen from the exhaust gases of an internal combustion engine, which liquid is contained in a tank, at least two electrically conductive measuring electrodes being at least partially embedded in a carrier that is produced of an electrically non-conductive material. The sensor arrangement includes a temperature sensor, especially a resistor with negative temperature coefficient being used as a temperature sensor, which is integrated into the carrier.
摘要:
A method for operating a metering valve and a device for performing the method, providing for diagnosis of the metering valve which defines a flow rate of a reagent to be introduced into an exhaust gas area of an internal combustion engine. The diagnosis is performed on the basis of an analysis of a measure for the flow rate during a diagnosis time. According to a first embodiment, after a diagnosis start signal has occurred with the metering valve closed, the reagent is brought to a predefined diagnosis starting pressure via a pump; the metering valve is then set at a predefined flow rate and the pressure difference occurring during the diagnosis time is analyzed. According to another embodiment, the amount of reagent delivered by the metering valve during the diagnosis time into a graduated beaker is analyzed.