Battery concern
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Joined: Sep 2022
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From: St Augustine, FL
E 350 Cabriolet, 2112
Battery concern
we have an 2012 E 350 Cabriolet that we garage and don't use a lot. Basically, it's the wife's car and she uses it a few times a week on short trips ( under 10 miles RT). Recently when starting the vehicle, it seems that the battery power is starting to sound like it's on its last legs. I took the car to one of the local part's place ( auto parts or the like) and had them test the battery. All OK, they said, but the battery charge is down to around 55%. Alternator, batter, all in good shape. I've tried taking it out and putting on a good short trip; e.g. 20 miles or so, but the condition soon returns after sitting in the garage for another 4-5 days. So, I believe I have to attribute the issue to lack of sustained use. I'm thinking that I should put a trickle charger on the car while it sits in the garage. I have a "Schumacher SC 1343" Battery Maintainer that has the "float" capability on it; i.e. just maintains the full charge after reaching it. Does anyone know if this type/model charger is safe to be connected to the 2012 Mercedes battery still connected to the car's system ?
Thanks in advance for your help.
Thanks in advance for your help.
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
If the car still has original batteries, that will make them 10 years old, and likely on their way out.
Not sure what battery health check was done to your battery, but the "MB approved" test at dealerships uses Midtronics equipment. I have seen some stores using such testers when checking batteries: SamsClub, Walmart, and Battery Plus. Some of them can print their reports, and you can then read the current CCA available. There is no amount of battery tender/charging that reliably guarantees an old battery will start every time your wife needs the car.
For your peace of mind, if the battery is the original, just change it and use the maintainer now. I have never used the Schumacher, I do own a CTEK (which seems to be the one MB uses)
Not sure what battery health check was done to your battery, but the "MB approved" test at dealerships uses Midtronics equipment. I have seen some stores using such testers when checking batteries: SamsClub, Walmart, and Battery Plus. Some of them can print their reports, and you can then read the current CCA available. There is no amount of battery tender/charging that reliably guarantees an old battery will start every time your wife needs the car.
For your peace of mind, if the battery is the original, just change it and use the maintainer now. I have never used the Schumacher, I do own a CTEK (which seems to be the one MB uses)
Thread Starter
Newbie
Joined: Sep 2022
Posts: 5
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From: St Augustine, FL
E 350 Cabriolet, 2112
Battery Concern
thank you for the reply, but the important question is can I use the trickle charger on the battery while it is still connected to the circuit in the car. If the battery does not fully charge up, then I know, it's going to need replacing.
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
I occasionally connect the trickle charger to the battery while it is still connected w/o issue. In fact, when using the XEntry diagnostic program, sometimes, I have it connected to the trickle charger as well.
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I use CTEK charger/maintainers as well connected directly to the battery while in the car without removing any connections. Your Schumacher is also designed for that type of operation to charge at a very low amperage and then maintain. Hook it up and see where it goes. I use the jumper terminals for easy access
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From: San Jose, CA
11 E550, 16 AMG GTS, 13 S550
if your battery is more than 3 years old I highly recommend changing it before it could potentially leave you stranded somewhere. You can charge it and maintain it properly now, but the damage has been done already and the capacity is permanently less than it would be. Batteries don't like being discharged for an extended amount of time and it hurts them. Also there is just nothing you can do about time. Normally your drives every 4-5 days would probably be enough to keep one going. It being cold doesn't always help either
But yes you can trickle charge it while attached to the car, it's how they were intended to be used.
But yes you can trickle charge it while attached to the car, it's how they were intended to be used.
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
I use a NOCO Genius charger, hook it up to the + terminal and ground post that are right there so I don't have to remove the battery cover... The Genius 10 is both a 10 amp smart charger AND a battery tender. when the battery is 100% charged, it reverts to tender mode, and even if your power fails, when the power comes back on, it resumes in tender mode automatically.
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From: New Orleans Area
2015 E400 Sedan
use your Schumacher SC 1343 tcharger as that is what it was designed for.
TO keep battery fresh as car sits.
1.5A 6V/12V Fully Automatic Battery Companion® | Schumacher Electric
TO keep battery fresh as car sits.
1.5A 6V/12V Fully Automatic Battery Companion® | Schumacher Electric
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From: Pepper Pike Ohio
24 GLS580 '23 E450 4matic 12 E350 4Matic
For a deaper dive into understanding the "Smart" charging system, SPrihadi has done a very comprehensive study, I believe the system charges to 80% of full capacity to leave room for "regenerative braking" which just means the alternator charges more when braking and coasting. I also charge using a trickle charger if I'm not driving the car for awhile, my '12 usually sits during the winter, so I start it and drive it a little in between the snow storms when the roads are dry and mostly salt-less. We drive the '13 all winter.
Last edited by pierrejoliat; Jan 7, 2023 at 01:36 PM.
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From: Dallas-Ft.Worth,TX
2016 E350 Sport
In my two-car garage, both vehicles are used alternately, to keep the batteries in some health, especially during Winter months.
In my W212, the Comand system refuses to boot up at engine start (when working at shutdown) when the battery is low. This is my indication that the battery charge is depleting. No tunes on engine start > time to recharge the battery.
I keep a Stanley battery charger on a stand between both cars. The Mercedes has never failed to start, even when "low," although the Shanley charger sometimes shows just 20-25% charge state when first connected. The main battery is now 3 years old, and I have learned to accept the constant energy depletion in this 4-wheeled computer.
For my Birthday in Nov., I treated myself to this highly-rated GOOLOO GT3000 (3000A 100W) Jump Starter/Battery Pack. Available at Amazon.com.
The 8 year-old battery in my 2014 Hyundai Sonata failed to start the car just 3 weeks ago, and the stand-alone GOOLOO could not have been easier to use with excellent results. It works a peach without a jumper car in sight, so I will take it with me for long distance travel in future, along with back-up jumper cables in both cars, of course.
In short, there are plenty of emergency solutions available today, so I think it unlikely that a dead battery will ever strand me alongside the road in future. And I can easily recharge the battery in either car when I park it in the garage at home.
In my W212, the Comand system refuses to boot up at engine start (when working at shutdown) when the battery is low. This is my indication that the battery charge is depleting. No tunes on engine start > time to recharge the battery.
I keep a Stanley battery charger on a stand between both cars. The Mercedes has never failed to start, even when "low," although the Shanley charger sometimes shows just 20-25% charge state when first connected. The main battery is now 3 years old, and I have learned to accept the constant energy depletion in this 4-wheeled computer.
For my Birthday in Nov., I treated myself to this highly-rated GOOLOO GT3000 (3000A 100W) Jump Starter/Battery Pack. Available at Amazon.com.
The 8 year-old battery in my 2014 Hyundai Sonata failed to start the car just 3 weeks ago, and the stand-alone GOOLOO could not have been easier to use with excellent results. It works a peach without a jumper car in sight, so I will take it with me for long distance travel in future, along with back-up jumper cables in both cars, of course.
In short, there are plenty of emergency solutions available today, so I think it unlikely that a dead battery will ever strand me alongside the road in future. And I can easily recharge the battery in either car when I park it in the garage at home.
Last edited by DFWdude; Jan 8, 2023 at 09:17 AM.
Member
Joined: Apr 2022
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From: Medina Ohio
2022 GLE
I use a NOCO Genius charger, hook it up to the + terminal and ground post that are right there so I don't have to remove the battery cover... The Genius 10 is both a 10 amp smart charger AND a battery tender. when the battery is 100% charged, it reverts to tender mode, and even if your power fails, when the power comes back on, it resumes in tender mode automatically.
