Have Mercedes Questions? Ask a Mechanic for Answers ASAP
Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.
On this model a dealer uses their SDS ( star diagnosis machine ) which has a program to track the component draining the battery.They plug this into your vehicle and enter a program that quickly identifies the drain.There is an older procedure I have used several times in the past before to help pinpoint it and it may or may not work on your model.It does require the use of a multi meter to locate the source of the drain.If you would like to know this procedure let me know and I can post it below.
As for the power outlet not working this is usually just a blown fuse needing replaced.Unfortunately my diagrams are not listing the fuse for this power outlet.I would check all fuses for any blown fuses needing replaced.
If you hear a component running with the key off this can be a cooling fan for a fuse panel that is stuck on needing replaced causing the drain here.This can be common.
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Let me double check this
O.k.,fuse 73 or 71 is the power source for the front and rear power outlets ( rear if equipped).I did some more research to locate this as well.Check and see if in the rear fuse panel either of these fuses are blown.Usually this wont cause the battery drain though but I would locate and replace the blown fuse and see if the issue still continues.
If it does then the battery drain testing needs done to pinpoint and repair this drain issue.
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