Battery’s gone just after two years
MBWorld Fanatic!
Joined: Apr 2006
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From: Dallas-Ft.Worth,TX
2016 E350 Sport
From Popular Mechanics:
The thing that kills batteries is heat, because it boils off the water in the electrolyte and hastens the sulfation process. That's when some of the lead on the plates of a partially discharged battery oxidizes into lead sulfate. The lead sulfate interferes with the normal charge-discharge chemistry of the battery, reducing capacity until finally you can't start your car.
Although most of the damage is done in the summer, the batteries customarily fail in colder weather. That's because cold oil is thicker than warm oil, and therefore demands more from the starter motor. Similarly, your car's electrical demands are higher in winter because you're running lights and window defrosters and windshield wipers more frequently.
The thing that kills batteries is heat, because it boils off the water in the electrolyte and hastens the sulfation process. That's when some of the lead on the plates of a partially discharged battery oxidizes into lead sulfate. The lead sulfate interferes with the normal charge-discharge chemistry of the battery, reducing capacity until finally you can't start your car.
Although most of the damage is done in the summer, the batteries customarily fail in colder weather. That's because cold oil is thicker than warm oil, and therefore demands more from the starter motor. Similarly, your car's electrical demands are higher in winter because you're running lights and window defrosters and windshield wipers more frequently.
I probably need to check the W212, as CarFax shows previous owner replaced a battery under warranty at 20 months (13K miles). But the report doesn't show if it was the Main or Aux. battery.
Newbie
Joined: Jul 2018
Posts: 11
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From: jacksonville, fl
E350 4matic 2010
My original MB battery in the 2010 E350 4M is sealed so no way to check the fluids inside. But it definitely gets a workout in the summer with the heat and AC running whenever I'm driving it. That's why I got the
CTEK MUS 5 battery charger.
CTEK MUS 5 battery charger.
Senior Member
Joined: Jul 2013
Posts: 308
Likes: 76
2024 E350
I have a 2012 E and I am still on my original battery. Knock on wood. I use a
a few times a year to top up the battery overnight. You can get it on Amazon for $45. I don't have to commute everyday, but when I do drive it's usually on the highway with each trip being over 30 miles. I haven't had any issues so far. Approaching 100,000 miles.
Newbie
Joined: Jul 2018
Posts: 11
Likes: 0
From: jacksonville, fl
E350 4matic 2010
Good news, I hope my will last that long. I do mostly shorter trips and the fla heat is brutal on batteries. But it is great to know that I should get 100k miles out it 
My only problem now
is the key fob stopped working and won't remote unlock or lock the doors, trunk, or gas flap.
My only problem nowis the key fob stopped working and won't remote unlock or lock the doors, trunk, or gas flap.
Senior Member
Joined: Jul 2013
Posts: 308
Likes: 76
2024 E350
Good news, I hope my will last that long. I do mostly shorter trips and the fla heat is brutal on batteries. But it is great to know that I should get 100k miles out it My only problem now
is the key fob stopped working and won't remote unlock or lock the doors, trunk, or gas flap.
My only problem nowis the key fob stopped working and won't remote unlock or lock the doors, trunk, or gas flap.
Junior Member
Joined: Aug 2014
Posts: 55
Likes: 6
From: Sarasota, FL
2011 E350
Most of my driving is under 20 minutes as I have a short commute and most stores I frequent are within 10 minutes. While exploring my occasional battery issues (fixed with replacing the almost 5 year old original battery), I started to use a external battery charger and take regular voltage readings to monitor the state of charge. I found that a full SOC would only last a couple of days and then the car would maintain itself at about 50-60%. I would always check in the morning after leaving the hood unlatched overnight to avoid using any batter power to open the door to release it. I was charging every few weeks and even took it out of the car to charge/recondition once but threw in the towel after that wasn't enough to keep it going.
After I got a new Bosch battery from Pep Boys (4 year warranty), I continued to use my charger and take readings. Even with a brand new battery, the car still maintains the battery at a 50-60% SOC. I have found that to be the case even after long drives as well as my regular routine.
When I started having MB battery issues, I started to monitor the battery in my wife's Honda for comparison sake. She drives shorter trips with most less than 5 minutes and starts her car probably twice as much as I do during a normal day. The Honda maintains an 80-90% SOC on a 2 year old battery (similar capacity but non AGM). Whenever I charge mine, I charge hers right after and her car is able to maintain the 100% for weeks.
So, based on my experience, I'm pointing my finger at MB for the design flaw they chose to save fuel or whatever reason rather than the battery itself. Now I admit that my experiment was not scientific and I am not an engineer, but I feel like I cannot trust my car to maintain the battery like the Honda can. So I continue to charge them both every few weeks in the hopes of avoiding a problem sooner than expected.
After I got a new Bosch battery from Pep Boys (4 year warranty), I continued to use my charger and take readings. Even with a brand new battery, the car still maintains the battery at a 50-60% SOC. I have found that to be the case even after long drives as well as my regular routine.
When I started having MB battery issues, I started to monitor the battery in my wife's Honda for comparison sake. She drives shorter trips with most less than 5 minutes and starts her car probably twice as much as I do during a normal day. The Honda maintains an 80-90% SOC on a 2 year old battery (similar capacity but non AGM). Whenever I charge mine, I charge hers right after and her car is able to maintain the 100% for weeks.
So, based on my experience, I'm pointing my finger at MB for the design flaw they chose to save fuel or whatever reason rather than the battery itself. Now I admit that my experiment was not scientific and I am not an engineer, but I feel like I cannot trust my car to maintain the battery like the Honda can. So I continue to charge them both every few weeks in the hopes of avoiding a problem sooner than expected.
MBWorld Fanatic!
Joined: Nov 2009
Posts: 2,616
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From: Southeastern USA
2010 E350 Luxury Sedan, Engine 272 (V6)
Picking up an old thread. My husband has been putting a charger on my W212 2011 E350 nightly for a year because he doesn't want me to get stranded (again). The car charges to 64% (even with a new battery) and then he tops it off with the charger. My mechanic says there's nothing wrong: No phantom drain, and the engine is charging the battery properly. So are we just being paranoid and should not go to the trouble of charging the battery nightly?
Do not do any charging on either battery, but keeping my fingers crossed with the M-B. I do make it a point to drive the M-B more and to drive it on longer trips, such as 40-50 mile round-trips about twice per month.
To me the issue is why can't M-B provide a 4-5 year warranty on a battery that costs twice as much as comparable ones?
MBWorld Fanatic!
Joined: Feb 2014
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From: MA
2008 E350 4Matic, 2011 E350 4matic
Picking up an old thread. My husband has been putting a charger on my W212 2011 E350 nightly for a year because he doesn't want me to get stranded (again). The car charges to 64% (even with a new battery) and then he tops it off with the charger. My mechanic says there's nothing wrong: No phantom drain, and the engine is charging the battery properly. So are we just being paranoid and should not go to the trouble of charging the battery nightly?
Junior Member
Joined: Aug 2014
Posts: 55
Likes: 6
From: Sarasota, FL
2011 E350
64% battery charge won't work in Minnesota
Lots of car manufacturers have been doing this lately. They just don't fully charge the battery so they can get better gas mileage for CAFE purposes. Every day is probably overkill but you could get a volt meter and see what the battery voltage is and figure out how often you need to charge it. I think there was a way to display the battery voltage in the display but it's not that easy a procedure and I forget how it's done on the W212.
Junior Member
Joined: Aug 2014
Posts: 55
Likes: 6
From: Sarasota, FL
2011 E350
Easier way to charge battery
If I have to accept that my battery will not charge above 64% on my 2011 E350 W212, and I have to charge the battery each night, my mechanic recommended I get an Interstate Battery CTEK charger that will sit on top of the plastic case that covers the battery. We had removed that because we are hooking up the charger every night. The mechanic said we should keep the case on the battery because of the source of air flow. Anyway, I can't figure out which CTEK model he was talking about that makes it possible to leave the case on. He said Mercedes charges $350 for the same model that he got (at cost) at Interstate for $80, so I guess retail would be about $120. Anyone using this charger? Thanks for all your help!!
MBWorld Fanatic!
Joined: Mar 2014
Posts: 3,107
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From: West Central Florida
2011 E550 P2 4M Sedan
If I have to accept that my battery will not charge above 64% on my 2011 E350 W212, and I have to charge the battery each night, my mechanic recommended I get an Interstate Battery CTEK charger that will sit on top of the plastic case that covers the battery. We had removed that because we are hooking up the charger every night. The mechanic said we should keep the case on the battery because of the source of air flow. Anyway, I can't figure out which CTEK model he was talking about that makes it possible to leave the case on. He said Mercedes charges $350 for the same model that he got (at cost) at Interstate for $80, so I guess retail would be about $120. Anyone using this charger? Thanks for all your help!!
You have to understand that anytime you charge your battery, the MB charging system is just going to use up that excess power during the next drive cycle by running the alternator at a lower output to save fuel and still leave you back at ~60% SOC again. If you want peace of mind then I would plan on replacing your battery when it starts showing its age. If your car is in Sarasota year round, I would think a typical AGM battery would would last about 3 to 4 years.
If you're worried about getting stranded (again), hopefully you have AAA but you might also want to carry around one of these little jump packs like this . That's how I kept jumping my own car when the battery was going out on me. Very easy to use to jump the car yourself.
MBWorld Fanatic!
Joined: Jan 2009
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From: V E G A S
1922 Ford Model T / no OBD
W212 has technology break-thru and newer models have so-called "smart charging".
It uses pretty advanced program to recoup braking energy for better mpg and less pollution. The side effect is that constant discharging/charging is killing the batteries faster and it is very hard to troubleshoot the charging system.
So as long as your car starts on cold morning, you should not worry about it.
Charging smart system in garage is fooling the computer, who expects long charging after overnight stop and when finds there is not much to charge - thinks the battery lost it capacity, what can results in codes.
Hard to fight with computers.
It uses pretty advanced program to recoup braking energy for better mpg and less pollution. The side effect is that constant discharging/charging is killing the batteries faster and it is very hard to troubleshoot the charging system.
So as long as your car starts on cold morning, you should not worry about it.
Charging smart system in garage is fooling the computer, who expects long charging after overnight stop and when finds there is not much to charge - thinks the battery lost it capacity, what can results in codes.
Hard to fight with computers.
Junior Member
Joined: Aug 2014
Posts: 55
Likes: 6
From: Sarasota, FL
2011 E350
Thank you so much! I decided to try this gizmo
Junior Member
Joined: Aug 2014
Posts: 55
Likes: 6
From: Sarasota, FL
2011 E350
Thanks so much for the idea -I got this (good reviews) https://www.walmart.com/ip/Everstart...ng-Case/876877
MBWorld Fanatic!
Joined: Mar 2014
Posts: 3,107
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From: West Central Florida
2011 E550 P2 4M Sedan
MBWorld Fanatic!
Joined: Dec 2011
Posts: 1,273
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From: Orlando, FL
2015 GL550 4matic
Advance Auto gold battery with 3yr warranty for about $120 has been going strong a little over 2 years in hot FL weather. Wife's Nissan just had battery failure on 3yr battery. It was 3 years and 1 month old, go figure! They design them this way, that's why I never consider any Warranty in buying decisions. The house (seller) almost always wins.
Senior Member
Joined: Dec 2016
Posts: 343
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E250 Diesel
Maybe this is the attachment the mechanic was talking about. Just screw on the battery terminal.
https://www.amazon.com/CTEK-56-382-C...dp/B002MT8S7E/
https://www.amazon.com/CTEK-56-382-C...dp/B002MT8S7E/
MBWorld Fanatic!
Joined: Feb 2014
Posts: 6,190
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From: MA
2008 E350 4Matic, 2011 E350 4matic
I think there was a way to display the voltage on the dash somehow. Not exactly sure how it's done though, lost track of that thread. You could do it on the W211 but I never actually did it on the W212.
As for that gadget, it can only tell you what the voltage of the battery is. Doesn't tell you if it's bad or not. To do that, you would have to get it load tested and most auto parts store will do it for free. Basically they put a load on the battery and see how long it takes for it to recover. If it's too long, it's bad.
As for that gadget, it can only tell you what the voltage of the battery is. Doesn't tell you if it's bad or not. To do that, you would have to get it load tested and most auto parts store will do it for free. Basically they put a load on the battery and see how long it takes for it to recover. If it's too long, it's bad.
Member
Joined: Aug 2017
Posts: 85
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From: LA
E350
Color marking on the indicator panel per Ctek site.
GREEN: battery voltage is over 12.65 = battery is fully charged and does not require charging.
YELLOW: battery voltage is between 12.65 and 12.4V = battery is well charged. Recharge if you have time and opportunity.
RED: battery voltage is below 12.4V = time for charging to prevent battery damage.
It does not tell you if you need to replace the battery. =(
GREEN: battery voltage is over 12.65 = battery is fully charged and does not require charging.
YELLOW: battery voltage is between 12.65 and 12.4V = battery is well charged. Recharge if you have time and opportunity.
RED: battery voltage is below 12.4V = time for charging to prevent battery damage.
It does not tell you if you need to replace the battery. =(
Senior Member
Joined: Dec 2016
Posts: 343
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E250 Diesel
Color marking on the indicator panel per Ctek site.
GREEN: battery voltage is over 12.65 = battery is fully charged and does not require charging.
YELLOW: battery voltage is between 12.65 and 12.4V = battery is well charged. Recharge if you have time and opportunity.
RED: battery voltage is below 12.4V = time for charging to prevent battery damage.
It does not tell you if you need to replace the battery. =(
GREEN: battery voltage is over 12.65 = battery is fully charged and does not require charging.
YELLOW: battery voltage is between 12.65 and 12.4V = battery is well charged. Recharge if you have time and opportunity.
RED: battery voltage is below 12.4V = time for charging to prevent battery damage.
It does not tell you if you need to replace the battery. =(
So, what gives??? why does my car lose charge overnight???? Technically speaking, it didn't even hit freezing temps the night before.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,225
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From: V E G A S
1922 Ford Model T / no OBD
With new cars complexity lot of things can go wrong.
Typical for bluetooth owners who park in garage attached to the house is not turning bluetooth off, so the car doesn't go to sleep still connected to the phone inside the house.
But batteries can be very tricky animals and the shop testers not always can figure out diminished capacity.
Just becouse the battery can crank 900 amp doesn't have to men it will do it for long.
Typical for bluetooth owners who park in garage attached to the house is not turning bluetooth off, so the car doesn't go to sleep still connected to the phone inside the house.
But batteries can be very tricky animals and the shop testers not always can figure out diminished capacity.
Just becouse the battery can crank 900 amp doesn't have to men it will do it for long.
