Auxiliary Battery Malfunction - Intermittent Warning
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2016 E350 4matic 2005 E55 Sedan
Auxiliary Battery Malfunction - Intermittent Warning
Having had my 2016 E350 sedan for about a week (about 40k miles), a gauge cluster message came up, "Auxiliary Battery Malfunction". I turned off the "ECO" button to prevent start/stop from draining any more battery in the meantime. The next day the warning went off and has remained off for about 2 days.
Is this something that can just wait until the message comes back up?
Thank you all!
Is this something that can just wait until the message comes back up?
Thank you all!
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
Having had my 2016 E350 sedan for about a week (about 40k miles), a gauge cluster message came up, "Auxiliary Battery Malfunction". I turned off the "ECO" button to prevent start/stop from draining any more battery in the meantime. The next day the warning went off and has remained off for about 2 days.
Is this something that can just wait until the message comes back up?
Thank you all!
Is this something that can just wait until the message comes back up?
Thank you all!
Better troubleshooting would be to do a good scan on the car to see if something else is wrong but a good simple starting point is the battery especially if it still is the original that came with the car from factory. It would be plenty old.
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2016 E350 4matic 2005 E55 Sedan
I would replace the AUX battery or at least have it tested. When that battery goes bad it takes out some features depending what options your car has.
Better troubleshooting would be to do a good scan on the car to see if something else is wrong but a good simple starting point is the battery especially if it still is the original that came with the car from factory. It would be plenty old.
Better troubleshooting would be to do a good scan on the car to see if something else is wrong but a good simple starting point is the battery especially if it still is the original that came with the car from factory. It would be plenty old.
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
if your car is a 2016, odds are the battery was new in 2015-2016, so its 8-9 years old. VRLA/SLA/AGM batteries are good for 5-8 years.
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From: West Linn, Oregon
2011 E550 - 4Matic, 2008 ML550
Ceck your fitment, but this should be the battery you need.
I have a 2011 E550, w212 - should fit.
I have no affiliation with this seller- but will give you an idea on what you need. It takes about 5-10 mins to swap out. (if under the dash)
Cheers
I have a 2011 E550, w212 - should fit.
I have no affiliation with this seller- but will give you an idea on what you need. It takes about 5-10 mins to swap out. (if under the dash)
Cheers
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
A 2016 wagon likely has quite a bit larger aux battery under the rear deck near the spare tire.... I think these are like 12V 12AH or something, and they have larger terminals.
like this,
there's an identical sized motorcycle battery you can get from Yuasa and various others thats a fair bit cheaper and will fit, but they do NOT have the overflow drain hose attachment that the Mercedes original had. While AGM batteries are 'sealed', they CAN leak overflow acid under unusual conditions such as getting overcharged, if that happens, you really don't want that acid and its fumes inside your car and next to your rear SAM.
like this,
there's an identical sized motorcycle battery you can get from Yuasa and various others thats a fair bit cheaper and will fit, but they do NOT have the overflow drain hose attachment that the Mercedes original had. While AGM batteries are 'sealed', they CAN leak overflow acid under unusual conditions such as getting overcharged, if that happens, you really don't want that acid and its fumes inside your car and next to your rear SAM.
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
As the first step I would replace this battery as it is old (if original) and will totally fail soon.
You do not need to go to dealer for this. Their battery is not any better, just costs twice as much.
My small AUX battery is in the end of the dash, but I think yours is either under the hood or in the trunk. Folks with 2016 models would know better but I think they are in a different forum...?
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Member
Joined: Jan 2011
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From: West Linn, Oregon
2011 E550 - 4Matic, 2008 ML550
Yes, you are Correct - its a AUX14 battery for the newer years!
Would recommend an AGM battery, they overall seem to last longer even if you pay a little more.
Cheers!
Would recommend an AGM battery, they overall seem to last longer even if you pay a little more.
Cheers!
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
MBWorld Fanatic!
Joined: Dec 2020
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
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2008 E350, 2012 ML350, 2014 E350, 2015 ML350
careful mixing terminology
An Sealed Lead Acid, SLA, battery is NOT necessarily an AGM battery
A Valve Regulated Lead Acid battery, VRLA, is not necessarily an AGM battery
However, most, if not all AGM are sealed and kind of valve regulated
https://www.midtronics.com/blog/the-...rtant-to-know/
An Sealed Lead Acid, SLA, battery is NOT necessarily an AGM battery
A Valve Regulated Lead Acid battery, VRLA, is not necessarily an AGM battery
However, most, if not all AGM are sealed and kind of valve regulated
https://www.midtronics.com/blog/the-...rtant-to-know/
Last edited by JCM_MB; Nov 3, 2024 at 05:46 PM.
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Lead-acid HYDROGEN venting...
Make sure your MAIN/AUX batteries are vented outside the same way Mercedes intended.
The trunk AUX is not compatible with sealed outdoor recreational sport batteries as it lacks proper venting.
Application type is also different than starter only. Our cars can deep discharge MAIN/AUX through ECO Cycles... that helps kill AUX because its charge current is not measured nor regulated.
Don't let all the cumulated ECO savings cost you big...
The trunk AUX is not compatible with sealed outdoor recreational sport batteries as it lacks proper venting.
Application type is also different than starter only. Our cars can deep discharge MAIN/AUX through ECO Cycles... that helps kill AUX because its charge current is not measured nor regulated.
Don't let all the cumulated ECO savings cost you big...
Last edited by CaliBenzDriver; Nov 3, 2024 at 06:37 PM.
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
I think reason for AGM batteries is safety during accidents as the acid soaked in the spongy glass mats is somewhat controlled from spraying on people if the battery cracks open during a collision.
A normal lead/acid battery works just fine with these cars and allows higher charging level of the battery too. MB uses smart charging that keeps batteries at like 85% or even lower charge level and it probably is because the AGM battery does not like full charge.
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
AGM batteries use antimony doped lead, which has slightly higher charge voltages, and the regulating valve does NOT allow that hydrogen to escape during normal operations, it lets the battery keep several PSI of pressure internally, then reabsorb the H2 when they are cooled down and discharging. If the H2 escaped, you'd need to replenish the water inside, and there's no way to do that with AGM/VRLA.
There's no true SLA battery, that term is sometimes used but its a misnomer, VRLA (Valve Regulated Lead Acid) is the proper name.
AGM batteries can also be mounted and used at any angle, they don't have to be upright. now, I don't know if the aux battery on the facelift 212s is sideways mounted or not, I was going to dig out the back of my wife's wagon and take a pic earlier today, but it was full of clothes and stuff, so i left it alone.
Anyways, Mercedes specified AGM batteries for both th emain and aux, I'll stick with using AGM. Heck, my Ford truck (2019 Expedition) has and specifies an AGM main batt.
There's no true SLA battery, that term is sometimes used but its a misnomer, VRLA (Valve Regulated Lead Acid) is the proper name.
AGM batteries can also be mounted and used at any angle, they don't have to be upright. now, I don't know if the aux battery on the facelift 212s is sideways mounted or not, I was going to dig out the back of my wife's wagon and take a pic earlier today, but it was full of clothes and stuff, so i left it alone.
Anyways, Mercedes specified AGM batteries for both th emain and aux, I'll stick with using AGM. Heck, my Ford truck (2019 Expedition) has and specifies an AGM main batt.
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From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
The terminals in the trunk battery are on top so assume its mounted normally. Atleast on my e250.
Get the ones with the best warranty if ya care, most are made by the same people or by the same couple people. My e250 had its batteries replaced toward the beginning of its life and are still chugging along. Any more than a month idle and they need a charge. My truck can sit for a month no issues but it is a tradesman (lower level less electronics).
Get the ones with the best warranty if ya care, most are made by the same people or by the same couple people. My e250 had its batteries replaced toward the beginning of its life and are still chugging along. Any more than a month idle and they need a charge. My truck can sit for a month no issues but it is a tradesman (lower level less electronics).
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2016 E350 4matic 2005 E55 Sedan
Probably just the amount of time for the original aux. battery then... I looked at it today and it is a Mercedes-Benz OEM battery, but I couldn't find the date anywhere just a bunch of serial numbers it looked like.
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2016 E350 4matic 2005 E55 Sedan
Make sure your MAIN/AUX batteries are vented outside the same way Mercedes intended.
The trunk AUX is not compatible with sealed outdoor recreational sport batteries as it lacks proper venting.
Application type is also different than starter only. Our cars can deep discharge MAIN/AUX through ECO Cycles... that helps kill AUX because its charge current is not measured nor regulated.
Don't let all the cumulated ECO savings cost you big...
The trunk AUX is not compatible with sealed outdoor recreational sport batteries as it lacks proper venting.
Application type is also different than starter only. Our cars can deep discharge MAIN/AUX through ECO Cycles... that helps kill AUX because its charge current is not measured nor regulated.
Don't let all the cumulated ECO savings cost you big...
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
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From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
I turn it off every time I start the vehicle, personally I find it very annoying and it doesnt do any good for the vehicle or fuel mileage with the exception of being stuck for hours (which I have) in which case just turn the vehicle off. The usual grid lock is a stop start which means the most wear and tear you can do to your engine (starting it) is happening every 30 sec or so. Its all IMO though so do what ya want.
I also found leaving my car trans in S vs E doesnt cause a decrease in fuel mileage (city or freeway) and makes driving in town much better. Thats my experience with my om651.
I also found leaving my car trans in S vs E doesnt cause a decrease in fuel mileage (city or freeway) and makes driving in town much better. Thats my experience with my om651.
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2016 E350 4matic 2005 E55 Sedan
its more like $0.10 saved gas . I want to turn it off by default on both my Mercedes and Ferd but haven't found a simple and safe way on either car.. Typically, first long stop where its shut off the engine, i wait until the traffic in front of me starts rolling then I switch 'eco' off which starts the engine, then I can roll forward and for the rest of that trip, its forget about it.
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2016 E350 4matic 2005 E55 Sedan
I turn it off every time I start the vehicle, personally I find it very annoying and it doesnt do any good for the vehicle or fuel mileage with the exception of being stuck for hours (which I have) in which case just turn the vehicle off. The usual grid lock is a stop start which means the most wear and tear you can do to your engine (starting it) is happening every 30 sec or so. Its all IMO though so do what ya want.
I also found leaving my car trans in S vs E doesnt cause a decrease in fuel mileage (city or freeway) and makes driving in town much better. Thats my experience with my om651.
I also found leaving my car trans in S vs E doesnt cause a decrease in fuel mileage (city or freeway) and makes driving in town much better. Thats my experience with my om651.
