12V battery partially charged
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Super Member
Joined: Dec 2004
Posts: 635
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From: Raleigh, NC
2020 S560 4Matic
12V battery partially charged
I used to drive every day for an hour. Now it’s more like once a week for 30 minutes. App says 12V battery is partially charged. I’m about to go away for 3 weeks. Should I be concerned? I plan to drive it maybe 45 minutes tomorrow.
MBWorld God!
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If you are going away for 3 weeks and the vehicle is secure in a garage, turn on standby mode. That disables all communications to the MB servers which drains the battery and disable anti theft alarm but it extends the battery for a few weeks.
Thread Starter
Super Member
Joined: Dec 2004
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From: Raleigh, NC
2020 S560 4Matic
Are there two steps here, or one? 1) Turn on standby mode AND 2) Disable anti theft? Or does standby mode disable everything? I kind of like having the theft system on while I'm away.
MBWorld God!
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One step, standby mode disables anti-theft automatically, hence why I only recommend it turned on when the vehicle is in a secure location, since that is one of the ways the car conserves battery.
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If you don't want to go that route and you are concerned, you could put the vehicle on a trickle charger, or like you said, drive it on the highway for 60 minutes and then come back and park it. 3 weeks shouldn't be too bad after all.
MBWorld God!
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If you do leave the vehicle inside a garage and no one will obviously be home, remove the battery from both the spare and main key in case the key is too close to the car and it senses a signal, which keeps the vehicle awake.
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Thread Starter
Super Member
Joined: Dec 2004
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From: Raleigh, NC
2020 S560 4Matic
I'll turn on standby mode before I leave.
MBWorld God!
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OK thanks. Secure location? It's true that all someone has to do is break a window and go find the key. I guess if I turn on standby, I'll never know if the car is stolen until I get back? I do have a safe and could leave the keys in there.
I'll turn on standby mode before I leave.
I'll turn on standby mode before I leave.
To know if standby mode is activated, lock the door and see if the red anti theft alarm light is flashing (forgot where it is on a W222 but close to the clock I think), if the doors are locked and the light isn't flashing anti theft is disabled and is disabled by standby mode.
MBWorld God!
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I recommend installing a security camera in the garage that has a cloud service which you can remotely check on the vehicle at a distance. I recommend doing it for the entire house even, install various cameras, video doorbell etc. and subscribe to a subscription that allows you to monitor the house as long as there is internet.
Super Member
Joined: Nov 2016
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From: NYC
S63, GLE580, BV250
I wouldn't worry about it, keep a jump pack/battery in the car cabin somewhere (or airport/parking lots have them available w/ staff as its a common thing), familiarize yourself with opening the car with the physical key, and the jump start process in case the battery is flat dead. If you have a trickle charger to top off before leaving at the lot thats always a plus. If you are in NYC area I have a little solar panel battery top off thing I can loan you for your trip.
As mentioned above double click the lock button when you leave the car, I know it shuts the key down, not sure if it disables the vehicle's keyless/security functions.
As mentioned above double click the lock button when you leave the car, I know it shuts the key down, not sure if it disables the vehicle's keyless/security functions.
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From: Charlotte, NC
Had: 1987 300TD, Had: 2004 C230 Sport Sedan, Have: 2014 E350 Sport, Have: 2019 S450
I had a similar message in the app for several months.
Finally, while working on the car with the doors open and the ignition on, I got a warning about low battery, and there was a hidden code about battery resistance being high.
I finally swapped out the battery (5 years old at the time), and the app now shows fully charged, no battery resistance hidden code, and no more worries.
Finally, while working on the car with the doors open and the ignition on, I got a warning about low battery, and there was a hidden code about battery resistance being high.
I finally swapped out the battery (5 years old at the time), and the app now shows fully charged, no battery resistance hidden code, and no more worries.
Junior Member
Joined: Oct 2007
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From: Surprise AZ
AMG GTS, SL55, S560, GLC43
I had the same problem with my battery. No matter what I did, it would never be fully charged in the app. So I bought an OEM battery. Problem solved. Next was the Standby Mode. It will not let you get into standby mode if the battery isn't fully charged. A quick fix is to get a trickle charger and set it to 2 amps.
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I wouldn't worry about it, keep a jump pack/battery in the car cabin somewhere (or airport/parking lots have them available w/ staff as its a common thing), familiarize yourself with opening the car with the physical key, and the jump start process in case the battery is flat dead. If you have a trickle charger to top off before leaving at the lot thats always a plus.
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Thread Starter
Super Member
Joined: Dec 2004
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From: Raleigh, NC
2020 S560 4Matic
I’d like to find a reliable trickle charger that won’t damage the battery or the electronics. I’ll check my records to see when I last changed the battery.
Member
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From: The Racing Capitol of the World
2019 AMG S 65 and too many other vehicles to list here in this small box
Stand-By mode is not available if your battery is not fully charged.
Driving your car 30 minutes will not fully charge a low battery.
Buy a CTEK charger and use it religiously.
MBWorld Fanatic!
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From: Venice Florida
2018 S560
Yes agree with putting the battery on a good battery maintainer when away from the car more than a couple weeks. I’ve done this all along and I’m still on my original starter battery in the trunk 7 years later. I have replaced the Aux battery once in 7 years. I’m hopeful of getting at least 10 years out of my starter battery. Never any messages or anything and when driving it reads between 13.5 and 14.5 volts at times.
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W212 FL
I have got the same device with the Mercedes-Benz logo. However, don't get me wrong I don't mean to stir the pot but it says : BATTERY CHARGER FOR 12 V LEAD ACID BATTERIES . Well, can we used it for gel batteries ? This is probably a question for a different topic though
MBWorld Fanatic!
Joined: Jul 2013
Posts: 4,830
Likes: 772
From: Venice Florida
2018 S560
I have got the same device with the Mercedes-Benz logo. However, don't get me wrong I don't mean to stir the pot but it says : BATTERY CHARGER FOR 12 V LEAD ACID BATTERIES . Well, can we used it for gel batteries ? This is probably a question for a different topic though
Member
Joined: Nov 2024
Posts: 219
Likes: 97
From: The Racing Capitol of the World
2019 AMG S 65 and too many other vehicles to list here in this small box
I have got the same device with the Mercedes-Benz logo. However, don't get me wrong I don't mean to stir the pot but it says : BATTERY CHARGER FOR 12 V LEAD ACID BATTERIES . Well, can we used it for gel batteries ? This is probably a question for a different topic though
AGM (Absorbant Gas Mat) is also a lead acid battery.
Outside of the very few new exotic batteries available, all of the batteries you will find for automotive use is either lead-acid or lithium.
You will need a different charger if you want to go Lithium but all other Lead-Acid types will charge as expected with this type of CTEK.
