Abstract: The invention relates to a method for emptying a reducing agent delivery system belonging to an SCR catalytic converter, which comprises a delivery line and a return line, each line connecting a reducing agent tank to a delivery module, and which comprises a pressure line that connects the delivery module to a metering valve. The method comprises the following steps: closing (50) the metering valve, and switching the delivery module from a delivering function to a returning function, by switching (51) a switching valve from a first position to a second position. This enables a reducing agent solution to be returned (52) from the return line, the delivery line and the delivery module by means of the delivery module and the delivery line into the reducing agent tank. Subsequently, the metering valve is opened (53) and a reducing agent solution is returned (54) from the metering valve and the pressure line, and also from the return line, via the delivery line into the reducing agent tank.

Abstract: A method for adjusting a pressure sensor of an SCR system between a delivery pump and a dosing valve, with which the delivery pump is switched off during a switch-off phase of the SCR system and a pressure (pm) measured by the pressure sensor is detected at least during a section of the switch-off phase in which the delivery pump is switched off, and the adjustment of the pressure sensor is carried out by using the measured pressure (pm) as the reference pressure for the pressure sensor.

Abstract: The invention relates to a method for emptying a reducing agent delivery system belonging to an SCR catalytic converter, which comprises a delivery line and a return line, each line connecting a reducing agent tank to a delivery module, and which comprises a pressure line that connects the delivery module to a metering valve. The method comprises the following steps: closing (50) the metering valve, and switching the delivery module from a delivering function to a returning function, by switching (51) a switching valve from a first position to a second position. This enables a reducing agent solution to be returned (52) from the return line, the delivery line and the delivery module by means of the delivery module and the delivery line into the reducing agent tank. Subsequently, the metering valve is opened (53) and a reducing agent solution is returned (54) from the metering valve and the pressure line, and also from the return line, via the delivery line into the reducing agent tank.

Abstract: A method for adjusting a pressure sensor of an SCR system between a delivery pump and a dosing valve, with which the delivery pump is switched off during a switch-off phase of the SCR system and a pressure (pm) measured by the pressure sensor is detected at least during a section of the switch-off phase in which the delivery pump is switched off, and the adjustment of the pressure sensor is carried out by using the measured pressure (pm) as the reference pressure for the pressure sensor.

Abstract: A method for monitoring at least one part of an internal combustion engine based on a variable whose values characterize the operation of the part of the internal combustion engine during different states of the internal combustion engine, including: determining an actual pattern with the actual values of the variable during different states of the internal combustion engine which describe the actual operation of the internal combustion engine; providing a reference pattern for a known operation of the internal combustion engine, the reference pattern including reference values of the variable for different states of the internal combustion engine; and comparing the actual pattern to the reference pattern to determine a similarity between the actual operation and the known operation.

Abstract: A method for diagnosing a bypass valve in a bypass line for an intercooler in a supercharger for an internal combustion engine, including the following steps: ascertaining a value of an efficiency of the intercooler as the reference efficiency; actuating the bypass valve to open the bypass valve; ascertaining a value of a further efficiency of the intercooler as the diagnosis efficiency after actuating the bypass valve to open; and detecting a malfunction of the bypass valve when the absolute value of the deviation between the reference efficiency and the diagnosis efficiency is less than a specified threshold value.

Abstract: A method for monitoring at least one part of an internal combustion engine based on a variable whose values characterize the operation of the part of the internal combustion engine during different states of the internal combustion engine, including: determining an actual pattern with the actual values of the variable during different states of the internal combustion engine which describe the actual operation of the internal combustion engine; providing a reference pattern for a known operation of the internal combustion engine, the reference pattern including reference values of the variable for different states of the internal combustion engine; and comparing the actual pattern to the reference pattern to determine a similarity between the actual operation and the known operation.

Abstract: A method for diagnosing a bypass valve in a bypass line for an intercooler in a supercharger for an internal combustion engine, including the following steps: ascertaining a value of an efficiency of the intercooler as the reference efficiency; actuating the bypass valve to open the bypass valve; ascertaining a value of a further efficiency of the intercooler as the diagnosis efficiency after actuating the bypass valve to open; and detecting a malfunction of the bypass valve when the absolute value of the deviation between the reference efficiency and the diagnosis efficiency is less than a specified threshold value.