In 2006, I bought a certified 2004 BMW 325xi. After about a year, the cooloant light came on, and the BMW service manager said this is common on this vehicle. Hew said just top it off which I did. Is there a bigger problem he is not telling me about. There are no leaks.
BMW 325 xi coolant level. on 2004 BMW 325i
Asked by for the 2004 BMW 325i
The cooling system in any car is a sealed system and shouldn't really require frequent topping up. I would suggest having the cooling system "pressure tested" if the level falls again. To pressure test the cooling system the filler cap is removed and the system is pressurized with a device that is similar to a bicycle pump. With the system pressurized the cooling system is inspected for leaks. BMW do have some plastic housing that deteriorate with age and heat cycling.