12V Battery?
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GLS 450 (2022), EQE SUV 350 (2025). GLS 450 (2007)
12V Battery?
Hi folks. I've got a 2025 EQE SUV 350 and have read that in addition to the main propulsion battery, this vehicle also has a conventional 12 V battery. Can anyone tell me where this is located in the vehicle and what its intended function is? Also, assuming that it does actually exist, is it charged by the main battery or by the wallbox charger? Thank you very much.
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From: Sweden
2023 EQE SUV 500 4Matic
Hi folks. I've got a 2025 EQE SUV 350 and have read that in addition to the main propulsion battery, this vehicle also has a conventional 12 V battery. Can anyone tell me where this is located in the vehicle and what its intended function is? Also, assuming that it does actually exist, is it charged by the main battery or by the wallbox charger? Thank you very much.
It is charged by the HV battery
In general, it provides power to all things that are not propulsion-related. Most importantly, it's needed to START the car.
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2011 SL550
my car ended up sitting for a bit because of my brakes, before that I had just replaced the rear battery but was still getting a red battery sign and not all the electronics were working, anyone know whats causing this? currently none of the inside lights work and locks nor does the automatic window, it just stays slightly down when i shut the door
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EQE SUV AMG-line 350+
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2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
The car will not regularly engage the DC/DC converter to charge the 12V battery. That said, if you approach the car and the it "wakes up" because of your key, and the battery is low, it *will* engage the DC/DC if the battery is critically low. Overall, I wouldn't recommend any consumers on your 12V unless you drive daily, and even then, it may not be as advisable.
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From: A Dutchy Living in Marseille, France
EQE SUV AMG-line 350+
Thanks .
Seems there are mixed opinions about this .
Some people say it won't tax the 12v battery, others say it does.
Maybe better not to mess with my current setup (battery pack) , which gives me at least 4 days of park mode
Seems there are mixed opinions about this .
Some people say it won't tax the 12v battery, others say it does.
Maybe better not to mess with my current setup (battery pack) , which gives me at least 4 days of park mode
Last edited by Egonvdv; Mar 11, 2026 at 07:35 AM.
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2024 EQE AMG SUV . 2021 GLE AMG 63s Coupe
After having some issues with my 12 vt battery I decided to be pro active and add a bluetooth 12 vt monitor so that I can see the battery condition in real time in order to see if it is charging correctly.
This works like a charm...
Last edited by ronin amg; Apr 22, 2026 at 02:52 PM.
