2013 E550 (88k miles) Battery Drain issue
I've read through the forms but wondering what would be the best course of action to determine what kind of issues I should asker the dealership to look for.
For the last 2 weeks or so I've noticed the car having more and more trouble turning over at start. Sounded like a low battery issue, but the car would still start...until today.
Also, I noticed the last 3 to 5 times I started the car that the AC/Heat system would do a weird cycle through all of the venting modes (like foot-well only, then windsheild only, then all 3, then the normal summer AC setting to just dash vents....also seemed to always start in Heat instead of AC, but once cycled it would blow AC like normal)
Wondering if anybody else has had similar issues.
Thanks,
W.




- bad old battery,
- SAM's drain,
- bad alternator or
- half-bad starter brushes ???
> Start with a full charge cycle to see what difference it does with the starter cranking speed.
> Measure running voltage to witness a positive charge.
Last edited by CaliBenzDriver; Sep 20, 2022 at 06:49 PM.
Thanks for your help.




I'm just glad it was the battery and not something else.




I'm just glad it was the battery and not something else.

A new battery every 6 years is an easy way to keep things in good repair.




