2003 mercedes c240 once i start my car the engine fan goes on it markes collant on 2003 Mercedes-Benz C240

That the coolant is low what can be the problem i dont like that the fan is on every day that i turn on my car and its loud and its like aselerated pls let me know what i can do to fix the problem im a mechanic but never worked on this car so let me know

Asked by for the 2003 Mercedes-Benz C240
have cooling system pressure tested to determine leak
Where can i go to get that done because it doesnt leak any water or anything
any german car rep place should be able to handle that for u
But do u have any idea what it can be so i can try out and see if it stops