In principle, the diagnosis and repair went well. The costs were high, whether reasonable I can not judge. The existing warranty was credited, as far as I can see correct, but it covered only a small part of the costs. What is particularly odd is that about 2 weeks after every appointment (inspection, seasonal check or repair) at this garage, the engine oil warning light comes on. Either it is a big coincidence that there is always an oil change after every appointment (but this is not noticed and fixed directly during the appointment), or the control unit is programmed accordingly (so that it outputs the error shortly), or a corresponding reset is forgotten by the workshop.