Abstract: A method for checking the tightness of a tank system of a vehicle wherein one introduces, with the aid of a pressure source, an overpressure relative to the atmospheric pressure over a pregiven time interval alternately into the tank system and a reference leak of a defined size connected in parallel to the tank system and detects at least one operating characteristic variable of the pressure source when introducing the pressure into the tank system (tank measurement) as well as when introducing into the reference leak (reference measurement) and compares the tank measurement to the reference measurement and, when there is a deviation of the tank measurement from the reference measurement by a pregiven value, drawing a conclusion as to a leak, is characterized in that, when a conclusion as to a leak is drawn, introducing pressure into the tank system over a further time interval, lengthening the tank measurement, thereafter executing a renewed reference measurement and outputting a fault announcement “l

Abstract: In a method for checking the tightness of a tank-venting system of a vehicle, one tightly closes the tank by means of a blocking device after shutting off the vehicle. Thereafter, one detects the pressure, which develops in the tank system, with a pressure sensor and draws a conclusion as to a leak based on the pressure trace over time. An arrangement for checking the tightness in accordance with this method is suggested.

Abstract: An active charcoal filter (20) of a tank-venting system stores fuel vaporizing in a tank (10). In order to check the operability of the tank-venting system, a leakage diagnostic unit (60) having a pump (50) is provided wherein the pump (50) is connected downstream of a switchover valve (70). A reference leak (81) is arranged parallel to the switchover valve (70). The switchover valve (70) includes two switching positions I and II. In the position I, the pump (50) is pressure-conductively connected to the line (80) and then pumps ambient air into the line (80) through the reference leak (81). The pumped flow, which is present at the output (51) of the pump (50), is, in the position I of the switchover valve (70) pure ambient air and, in the position II of the switchover valve (70), is air cleaned by the active charcoal filter (20). The pumped flow can therefore be outputted to the ambient of the vehicle via a line (52) without problems for the environment.

Abstract: In a method and a device for leak testing of a vessel, e.g., a tank venting system of a motor vehicle, a leak-tightness measurement is performed by introducing a positive pressure or partial vacuum and detecting the variation over time of a positive pressure or partial vacuum in the vessel, and a reference measurement is performed using a reference leak. A conclusion is drawn as to the presence of a leak in the vessel by comparing the results of the leak-tightness measurement and the reference measurement. To avoid faulty diagnoses, the positive pressure or partial vacuum during the leak-tightness measurement and the reference measurement is detected by using a single pressure measuring device.

Abstract: The invention is directed to a method and an arrangement for detecting faults in the context of measurement quantities in a motor vehicle. At least one measurement quantity is represented by two redundant signal values. The time-dependent changes of the signal values are determined for fault recognition and a fault condition can be assumed when the signal changes no longer correlate with each other. The arrangement for fault recognition includes an input circuit of a control apparatus to which the measurement quantities are supplied via two lines from two measuring devices. One line is provided with a resistor to ground or to the supply voltage; whereas, the other line is configured without such a resistor or has a resistor to the supply voltage or to ground having an ohmage higher than the first resistor.

Abstract: A method for checking the tightness of a tank system, especially of a tank-venting system of a vehicle, wherein an overpressure or an underpressure relative to the atmospheric pressure is introduced into the tank system by means of a pressure source and the time-dependent trace of at least one operating characteristic variable of the pressure source is detected when introducing the overpressure/underpressure up to reaching a first time point or a first pressure level and is compared to a time-dependent trace of the operating characteristic value up to this time point or up to this pressure level (expected diagnostic trace), the time-dependent trace being expected in the case of a tight tank system, and, a conclusion as to non-tightness is drawn when the detected time-dependent trace deviates from the expected diagnostic trace by at least a pregiven value, characterized in that, when a deviation is determined, the overpressure/underpressure in the tank-venting system is further increased up to reaching a secon

Abstract: A method for checking the tightness of a tank system of a vehicle wherein one introduces, with the aid of a pressure source, an overpressure relative to the atmospheric pressure over a pregiven time interval alternately into the tank system and a reference leak of a defined size connected in parallel to the tank system and detects at least one operating characteristic variable of the pressure source when introducing the pressure into the tank system (tank measurement) as well as when introducing into the reference leak (reference measurement) and compares the tank measurement to the reference measurement and, when there is a deviation of the tank measurement from the reference measurement by a pregiven value, drawing a conclusion as to a leak, is characterized in that, when a conclusion as to a leak is drawn, introducing pressure into the tank system over a further time interval, lengthening the tank measurement, thereafter executing a renewed reference measurement and outputting a fault announcement “l

Abstract: The invention relates to a device for operating a fuel cell tank system of a motor vehicle which comprises a pump and valve assembly (11), an activated carbon filter (12), a fuel tank (14) and a control device (20). Said device also comprises safely valve, (31, 32) and a pressure switch (33). The assembly (11) contains a currentless bistable electromagnetic valve (40) which is connected to the control unit (20) via a line (41) and which can be controlled by a control module (42). The control unit (20) is connected to pressure and/or temperature sensors (45, 46) via lines (43, 44). The pressure sensors (45, 46) send pressure signals to the control unit (20) via said lines (43, 44).

Abstract: A method for checking the tightness of a tank system, especially of a tank-venting system of a vehicle, wherein an overpressure or an underpressure relative to the atmospheric pressure is introduced into the tank system by means of a pressure source and the time-dependent trace of at least one operating characteristic variable of the pressure source is detected when introducing the overpressure/underpressure up to reaching a first time point or a first pressure level and is compared to a time-dependent trace of the operating characteristic value up to this time point or up to this pressure level (expected diagnostic trace), the time-dependent trace being expected in the case of a tight tank system, and, a conclusion as to non-tightness is drawn when the detected time-dependent trace deviates from the expected diagnostic trace by at least a pregiven value, characterized in that, when a deviation is determined, the overpressure/underpressure in the tank-venting system is further increased up to reaching a secon

Abstract: The invention is directed to a method and an arrangement for detecting a changing quantity for a motor vehicle. The changing quantity is the position of an operator-controlled element. At least one stop value is determined for the operator-controlled element when released. Outside of the operation of the motor vehicle, this stop value is dependent upon the operation of a test apparatus connected to the control unit of the motor and/or when a defined state of the control unit and/or when there is a defined sequence of specific actuations of operator-controlled elements.

Abstract: The invention is directed to a method and an arrangement for detecting a changing quantity for a motor vehicle. The changing quantity is the position of an operator-controlled element. At least one stop value is determined for the operator-controlled element when released. Outside of the operation of the motor vehicle, this stop value is dependent upon the operation of a test apparatus connected to the control unit of the motor and/or when a defined state of the control unit and/or when there is a defined sequence of specific actuations of operator-controlled elements.

Abstract: A method and a device for controlling a drive unit of a vehicle in which the actual torque of the drive unit is compared to a specified, maximum allowable torque for monitoring purposes. When the actual torque exceeds the maximum allowable torque, the drive unit is controlled in a torque-reducing manner. The actual torque of the drive unit is determined on the basis of a signal representing vehicle acceleration. Instead of comparing absolute values, a differential comparison is carried out.

Abstract: A method and an arrangement for operating and monitoring an internal combustion engine are suggested wherein, in at least one operating state, operation is undertaken with a lean air/fuel ratio. At least one quantity, which represents the degree of actuation of the accelerator pedal, and a quantity, which represents the engine rpm, are detected and, in at least one operating state, only an operation of the engine with an approximately stoichiometric or rich mixture is permitted and/or only an operation with limited air supply is permitted. The operation is monitored on the basis of at least one operating variable of the engine.

Abstract: The invention is directed to a system for controlling a clutch which is arranged between the motor of a vehicle generating a motor torque and the wheels of the vehicle. With this clutch, and in response to a drive signal, the force flow between the motor of the vehicle and the wheels can at least be reduced. The essence of the invention is that the drive signal of the clutch is formed in dependence upon a signal which represents a change of the motor torque of a specific extent. The invention is also directed to a system for controlling the motor of a vehicle with an adjusting element for influencing the motor torque which can be adjusted at least in dependence upon the detected command torque. When a specific extent of a change of motor torque is present, the execution of the command to adjust the motor torque is delayed.

Abstract: A tank-venting system includes an active charcoal filter (20) which is connected to a tank (10) via a tank connecting line (12). An intake manifold (40) of an internal combustion engine is connected via a line (42) to a tank-venting valve (30). The active charcoal filter (20) stores fuel vaporizing in the tank (10). In order to check the operability of the tank-venting system, a leakage diagnostic unit (60) having a pump (50) is provided wherein the pump (50) is connected downstream of a switchover valve (70). A reference leak (81) is arranged parallel to the switchover valve (70). The switchover valve (70) includes two switching positions I and II. In the position I, the pump (50) is pressure-conductively connected to the line (80) and then pumps ambient air into the line (80) through the reference leak (81).

Abstract: A method and an arrangement for operating an actuator in a motor vehicle are proposed. A first and/or a second operating variable signal is determined and a fault check thereof is carried out. When a fault occurs, a first reaction is immediately initiated, which can represent, for example, a limiting of the adjusting speed and/or of the acceleration of the actuator. When the fault condition has been present for a longer time, a second reaction is initiated, which applies a substitute signal instead of the faulty one for control or which consists of a switching off of the actuator operation.

Abstract: A method and an arrangement for controlling a drive unit of a motor vehicle wherein at least one of the following quantities is determined: torque, power or throttle flap angle. This quantity is compared to the maximum permissible value and, when the maximum permissible value is exceeded by the determined quantity, fault reaction measures are initiated. The maximum permissible value is formed in dependence upon the time-dependent change of the rpm of the drive unit.

Abstract: A method and arrangement for controlling a drive unit of a vehicle are suggested. A desired torque value or a desired power value is formed on the basis of the driver command which serves to control the drive unit. A maximum permissible torque or a maximum permissible power is determined and the desired value is limited to the maximum permissible value when the desired value exceeds the maximum permissible value.

Abstract: The invention is directed to a system for controlling a clutch which is arranged between the motor of a vehicle generating a motor torque and the wheels of the vehicle. With this clutch, and in response to a drive signal, the force flow between the motor of the vehicle and the wheels can at least be reduced. The essence of the invention is that the drive signal of the clutch is formed in dependence upon a signal which represents a change of the motor torque of a specific extent. The invention is also directed to a system for controlling the motor of a vehicle with an adjusting element for influencing the motor torque which can be adjusted at least in dependence upon the detected command torque. When a specific extent of a change of motor torque is present, the execution of the command to adjust the motor torque is delayed.

Abstract: A method and an arrangement for controlling a drive unit of a vehicle are suggested. In this method, the control functions for the power of the drive unit and the monitoring of these control functions are carried out by a single microcomputer. A monitoring module, which is separate from the microcomputer, is provided for checking the monitoring functions. The monitoring module transmits test signals to the microcomputer at a given time. The microcomputer then computes the monitoring function on the basis of test data. The result of the computation is transmitted to the monitoring module which checks the operability of the monitoring function in the microcomputer by making a comparison to stored values.