N’Evening on all sides, I have been driving a V70 II D5 AWD for years and have been happy with 230000 self-propelled Kilmometers since now. Overall, he has now nearly 260000km down. For a few days I have been getting the error message “Motor system maintenance required” with a yellow triangle in the BC. There are also days when it does not occur. Now I was at the workshop of my trust (not a Volvo representative, but a free one) and we looked into the error memory once. In the engine control the errors 6661 and 6588 are stored. (The computer of the workshop says to both “unknown errors”, both can not be deleted). After inquiries from Mr. Google is probably 6661 the glow plug of the first cylinder – so actually nothing dramatic, I will let it happen on occasion. But to the code 6588 there is simply nothing to be found…. Can someone bring light into the dark here?