12v battery message
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Member
Joined: Sep 2009
Posts: 180
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From: California
E300
12v battery message
My brand new 2025 E350 has 50 miles on it. I haven't driven it in about 10 days. I'm getting a message through the Mercedes app on my iphone that the 12v battery is depleted. One message says to drive the car for 30 minutes to charge the battery. I tried starting the car and had no problem. is this 12v battery thing normal or is something wrong with my car? Should I take it for service? What can be done to prevent such messages if I park my car for a week or more? Thanks.
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Thread Starter
Member
Joined: Sep 2009
Posts: 180
Likes: 67
From: California
E300
Thanks. Where is this 12v battery in the 2025 E350 and how do you connect the charger? Also, are you saying there is nothing wrong with my car when it displays the 12v battery alert...that this is normal after several days of non use and doesn't require dealer service?
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Joined: Aug 2014
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From: Tennessee
W214 E450
My brand new 2025 E350 has 50 miles on it. I haven't driven it in about 10 days. I'm getting a message through the Mercedes app on my iphone that the 12v battery is depleted. One message says to drive the car for 30 minutes to charge the battery. I tried starting the car and had no problem. is this 12v battery thing normal or is something wrong with my car? Should I take it for service? What can be done to prevent such messages if I park my car for a week or more? Thanks.
Location for a battery tender has been covered here. And the exact problem you are having has been discussed here.
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From: DFW Texas
GL450, E450, Porsche 718 GTS
I mainly just do short trips around town and sometimes the car will sit for a couple of days at a time not being driven. Two days ago I decided to install the nav update in my car and hooked up my 4 amp Battery Tender to the battery while downloading. The download only took about 10 minutes but I went ahead left the charger on to top the battery off completely.
The Tender got hot and I could tell it was dumping the full 4 amps. It took five or six hours to top off the battery.
I’ve never had a battery warning but I suspect that these cars always have stuff going on even when they’re asleep.
Makes me wonder about all those new cars sitting on the lot for a month or so? Do the batteries go dead? Why is it necessary to use maintainers on the showroom floor?
The Tender got hot and I could tell it was dumping the full 4 amps. It took five or six hours to top off the battery.
I’ve never had a battery warning but I suspect that these cars always have stuff going on even when they’re asleep.
Makes me wonder about all those new cars sitting on the lot for a month or so? Do the batteries go dead? Why is it necessary to use maintainers on the showroom floor?
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MBWorld God!
Joined: Dec 2019
Posts: 33,395
Likes: 6,624
Thanks. Where is this 12v battery in the 2025 E350 and how do you connect the charger? Also, are you saying there is nothing wrong with my car when it displays the 12v battery alert...that this is normal after several days of non use and doesn't require dealer service?
Member
Joined: Nov 2021
Posts: 229
Likes: 72
From: Poland
GLE
My brand new 2025 E350 has 50 miles on it. I haven't driven it in about 10 days. I'm getting a message through the Mercedes app on my iphone that the 12v battery is depleted. One message says to drive the car for 30 minutes to charge the battery. I tried starting the car and had no problem. is this 12v battery thing normal or is something wrong with my car? Should I take it for service? What can be done to prevent such messages if I park my car for a week or more? Thanks.
MBWorld God!
Joined: Dec 2019
Posts: 33,395
Likes: 6,624
I mainly just do short trips around town and sometimes the car will sit for a couple of days at a time not being driven. Two days ago I decided to install the nav update in my car and hooked up my 4 amp Battery Tender to the battery while downloading. The download only took about 10 minutes but I went ahead left the charger on to top the battery off completely.
The Tender got hot and I could tell it was dumping the full 4 amps. It took five or six hours to top off the battery.
I’ve never had a battery warning but I suspect that these cars always have stuff going on even when they’re asleep.
Makes me wonder about all those new cars sitting on the lot for a month or so? Do the batteries go dead? Why is it necessary to use maintainers on the showroom floor?
The Tender got hot and I could tell it was dumping the full 4 amps. It took five or six hours to top off the battery.
I’ve never had a battery warning but I suspect that these cars always have stuff going on even when they’re asleep.
Makes me wonder about all those new cars sitting on the lot for a month or so? Do the batteries go dead? Why is it necessary to use maintainers on the showroom floor?
Yes, if a battery is overcharged that it caused damage, they need to replace it, of course they won't do so until a customer complains after delivery and won't do so unless it is covered by warranty, there is a reason why there were threads that said battery replacements (no W214 yet) that solved issues.
Thread Starter
Member
Joined: Sep 2009
Posts: 180
Likes: 67
From: California
E300
12v battery message
Thanks for all the advice. My car started with no problem despite the 12v low battery warning. I drove 15 minutes to the dealer and the warning went away. A service person looked at it and said this is normal. She showed me how to connect a charger and I just got one. Seems strange that a battery warning appeared after only a week or so of non-use and probably will appear again in the same situation, but all the gauges and other functions seemed to work .
MBWorld Fanatic!
Joined: Aug 2014
Posts: 1,952
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From: Tennessee
W214 E450
Thanks for all the advice. My car started with no problem despite the 12v low battery warning. I drove 15 minutes to the dealer and the warning went away. A service person looked at it and said this is normal. She showed me how to connect a charger and I just got one. Seems strange that a battery warning appeared after only a week or so of non-use and probably will appear again in the same situation, but all the gauges and other functions seemed to work .
Last edited by L1Wolf; Mar 9, 2025 at 03:23 PM.
Member
Joined: Nov 2021
Posts: 229
Likes: 72
From: Poland
GLE
Thanks for all the advice. My car started with no problem despite the 12v low battery warning. I drove 15 minutes to the dealer and the warning went away. A service person looked at it and said this is normal. She showed me how to connect a charger and I just got one. Seems strange that a battery warning appeared after only a week or so of non-use and probably will appear again in the same situation, but all the gauges and other functions seemed to work .
