Moin Moin, The heating of my C5 III BJ09 doesn’t want any more, i.e. no warm air reaches the interior. The temperature indicators in the car show both normal temperature only the water temperature goes up when standing or very slow driving (- Luefter runs long after…) On the highway he blew warm air once for a few minutes but then came cold air again. In addition, he shows me the message exhaust system defective. I can test/exchange or is there only the direct way to the workshop ? Thank me for all tips Experiences Opinions in advance MFG Dominik