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Frequently asked questions about cars and motorcycles

Error "backup battery anomaly" on Mercedes Class B.

Model: Mercedes Classe B MK 2, W246 - Years: 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019
Part: Warning light – error code

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Video tutorial

In this video, we will see how to behave if the message "backup battery anomaly" appears on the display of our Mercedes Class B. It is very likely that the auxiliary battery, which supports the large amount of electronic equipment in this vehicle, has been discharged.

The battery in question is located inside the passenger compartment, in the footwell on the passenger side.

So, we remove the mat, then going to the upper part of the compartment, we pull down the carpet, and we will be able to access the compartment where the auxiliary battery is located, inserted deep inside; in fact, to remove the door that covers it, we will have to remove a partition located in the lower part of the glove compartment.

The battery is secured with screws to its base, so we will have to unscrew it, remove the negative pole, then the positive one, remove the old battery - which we will dispose of at an authorized center, and replace it with the new one, proceeding in reverse.

We close the cap, put back the partition, then reposition the carpet and the mat.


Posted on 19 January 2025 by ScegliAuto


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Watch the video!


by ScegliAuto

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