battery dies every three days
What is killing my battery I have Aa 2000 Mercedes.clk everything works good I just
don't know what going on with. My battery and the battery is new
bad batteries usually can't hold a charge but, now, if the alternator is not charging it then, yeah. Those are the 2 possible reasons for your situation. Take the battery to get tested at an auto parts store and if ti's not the battery then, it's the alternator. You can also drive the vehicle to a shop and they can test both of them, without removing anything.
You've also posted a CLK question under ML section. This is a Universal question though.
Search Mercedes-Benz M-Class Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Mercedes-Benz M-Class Experts