2011 ml350 going CRAZY! plz help

Short of that, PERHAPS have the mechanic (or you) throw an automatic charger (not one of those jump-starter high amperage chargers) on the battery connections under the hood (see your manual re jump starting) at no more than 6 amps for a few hours on the AGM setting and see if it will even take a charge and if so whether it takes more than 4-5 hours to give a green light. Any more than 6 amps and the car will start to complain with buzzers, noises, etc.
On the W164, the battery will be fine until it isn't. And when it isn't, it doesn't just exhibit symptoms like failing to start the car. Instead, the "car goes crazy", with flashing lights, buzzers and other aural warnings you've never heard, a zillion warning messages, transmission issues, etc.
I just had this happen on our 2008 W164 a month ago. I eead about battery issues here, said to myself, "It can't be that simple!" Went to Advance Auto Parts and just bought a new H8 Platinum AGM Battery, which was on sale at the time, put it in myself (they will do it for free or a nominal charge, which I didn't know).
Problem solved.
Really. Just like that.
Putting a new battery in this car is a significant PITA. It's under the passenger seat, and there's a great Autohaus video on Youtube about how to change it, which is dead on and has several helpful tips which let me do it in about an hour. (I could do it way faster now having done it once, but I was careful the first time.) I have a detailed post on it in another thread here. https://mbworld.org/forums/m-class-w...50-4matic.html
This might not be your problem, but your symptoms, especially the "car is going crazy" comment, seems to fit.
Let us know how it goes.
Last edited by wjcandee; Feb 20, 2015 at 12:11 AM.






