Mercedes Repair Questions? Ask a Mechanic for Answers ASAP
No one will be able to remotely log in but that won't help me much any way. Do you know how to do a battery draw test or Quiescent current draw test on the battery? If not there are some common causes for battery drains on this model. The first are shorted tele-aid/phone call buttons located inside the center console. They can cause the phone module to try and make phone calls even though the car is off. The next thing I would do is to program the rear sam computer with the latest software. I would also make sure there is no water entry near the rear fuse box compartment or water in the battery compartment underneath the passenger front seat. If those are dry, I would replace the steering column module since these cause intermittent battery draws all the time. There is actually a service bulletin on them for this exact problem.
Let me know if you have any questions before you decide to rate me, thanks!