I have a 2004 BMW 745li
My heat is not getting hot and the low coolent
keep coming on but I have put some in it but still
Sounds like you may have a leak in the coolant system, and the thermostat needing to be replaced. Should find a shop to have the cooling system pressurized to find the leak, that is if you can't find it.
after you repair the leak, and you also have to bleed the system properly to stop it from overheating. If you overheat and get it hot too many times, you will damage the engine = $$$$.
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