Hi, I have a bit of experience with cars and had a similar problem with my VW Golf (petrol engine, built in 2005). The fault was the control unit for the parking heater. I went to my favorite garage and they repaired it for me. It cost me 440 euros. However, I can't give you any more details without exact vehicle data. Could you please provide more information, such as the exact equipment and mileage? That would help me to advise you better.

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Hey, thanks for your quick reply! So my Passat has standard equipment and has now covered 156234 km. Last service was about 5 months ago. Hope that helps you! How exactly can you find out if the control unit is really the problem?

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Well, with your further details, it's possible to do a bit more. With so many kilometers on the clock and the symptoms you describe, it sounds to me more like a problem with the cooling circuit. Perhaps the coolant level is too low due to a leak or something similar. Have you looked under the car to see if there's a puddle? That could be a sign. To be really sure, however, a visit to the workshop would probably be necessary. With the right diagnostic device, you can read out your car's fault memory and that will usually tell you what the problem is. I would suspect a problem with the thermostat or the water pump, but only a specialist can really assess this on site. Hope this helps you a little!

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Hello, thank you very much for your detailed reply and the helpful tips! I have indeed noticed a puddle under the car and will definitely have it checked at the garage. Your tip about the thermostat and the water pump sounds very plausible, so I'll pass that on to the experts there. Thanks again for your time and effort!

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