BeachBunny

Just curious, does anyone know how much % per day an E-Class will deplete it's battery(ies?) when it's parked?

The owner's manual has this ominous-sounding warning in it:

Egonvdv

the longest i leave my car is during holidays of 3 weeks, which is about once a year.
and it always starts up right away. - Never check at what level the batter was though...
If you put it in standby mode you lose the ability to track the vehicle and anti-theft won't work.
But if this is not a problem for you, then why not just put it in standby whenever you want?

c4004matic

MB vehicles have a myriad of systems that work even when the car is "off" they include airmatic, oil pumps, brakes, etc. In fact the car is never really off. Though they only use a trickle they do require the car to be used regularly to keep "healthy". If you are worried simply use a trickle charger if you are going to store the car for more than 3 weeks. They are very cheap. The main concern after a long period is the electronic parking brake. This is true of any parking brake regardless of type. If you are going to store the car for more than a few weeks, release the parking brake and chock one of the wheels with a ramp or 4x4. That will prevent the pad from rusting to the rotor.

BeachBunny

Just curious, what are people using for standby/trickle chargers? One of the local dealerships has every one of their showroom cars plugged into some sort of Mercedes-branded charger, although I suspect you can get the same charger elsewhere for less minus the MB sticker on the cover. Because of the electronics in an MB, I'd be afraid to connect a no-name Chinese charger to it.

c4004matic

Cars in dealerships sit sometimes for mths, thus trickle charging is essential. Not to worry trickle charger are simple cheap tech, even the 15 dollar Chinese on will do the trick. Pretty sure the MB one is the same cheapo with a badge upgrade.

rorywquin

The MB chargers are rebranded CTEK. But there is a big choice - not sure if there is a price difference

joshg1001

Might also want to inflate your tires a bit more if you are parking it for weeks.

c4004matic

For years I stored my s2000 for winter. All I did was disconnect the battery and block the wheels (no parking brake). After 6 mths, it always started like a song. Unfortunately new cars are never really "off" so that is not an option anymore. On our cars its almost impossible to do anything with the battery at all. Wnen I tuned my c400 disconnecting the battery took a gymnastics course since its basically inaccessible!

BeachBunny

Does anyone know how many batteries the E300 has? My W212 had 3... which seemed a bit much and failure-prone.

robert c

I wouldn't use a true trickle charger on those lead acid batteries. I use several Granite Digital 12 watt charger/maintainers on various types of batteries/vehicles and never a problem A trickle type usually produces a constant higher voltage that literally over charges most all batteries.

Cerave

I would like to know the answer to this as well.

2012 merc amg

Pretty sure it's just the main big battery under the hood at this point. There were so many complaints with the secondary motorcycle looking battery (starter battery) failing that MB went to a system using a big capacitor instead of a battery and it really simplified things. But ya, anymore than a couple weeks I'd go with a battery maintainer hooked up to the car. Keep in mind though even when the the app is telling you the battery is critically low there is still plenty of power left in it, I think it's some kind of software bug.

whoover

No Mercedes had three. The 213 is the same as the 212: a main "starter" battery and an auxiliary "system" battery. The auxiliary battery is now not really a battery, but a supercapacitor bank that serves the same function as a battery and is still referred to as the auxiliary battery (for instance in dash error messages). It's located in the passenger footwell area.

Your "three batteries" might be confusion because early 212s had a small "motorcycle" battery in the drivers knee area as the auxiliary battery. Later models switched to the supercap bank in the passenger footwell. No car had both.