Method for operating a drive device for a motor vehicle and corresponding drive device

A method for operating a drive device for a motor vehicle, wherein the drive device has an exhaust-gas-generating drive unit, and by an exhaust gas probe an exhaust gas value describing a composition of the exhaust gas is determined, and for a plurality of systems of the drive device a state value describing the state of the respective system is determined, in each case as part of a system diagnosis, wherein, for each of the plurality of systems, it is defined in at least one system defect data set whether a system defect of the respective system affects the exhaust gas value, wherein if the exhaust gas value departs from an exhaust gas range, the system defect data sets of the systems are first put on a checklist of system defect data sets to be checked, and then, those system defect data sets for which it is defined that the exhaust gas value is not affected are removed from the checklist, wherein for the system defect data sets remaining on the checklist, a device diagnosis is carried out to detect the system defect of the respective system based on the state value.

A drive device for a motor vehicle, in particular for executing the method according to one or more of the preceding claims, wherein the drive device has an exhaust-gas-generating drive unit, and is provided and designed to determine, by an exhaust gas probe, an exhaust gas value describing a composition of the exhaust gas, and to determine, for a plurality of systems of the drive device, a state value describing the state of the respective system, in each case as part of a system diagnosis, wherein, for each of the plurality of systems, it is defined in at least one system defect data set whether a system defect of the respective system affects the exhaust gas value, wherein the drive device is further provided and designed to put, if the exhaust gas value departs from an exhaust gas range, the system defect data sets of the systems firstly on a checklist of system defect data sets to be checked, and then to remove those system defect data sets for which it is defined that the exhaust gas value is not affected from the checklist, wherein for the system defect data sets remaining on the checklist, a device diagnosis is carried out to detect the system defect of the respective system based on the state value.