Will charger charge both batteries
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2017 GLE 350 4M
Will charger charge both batteries
I occasionally put a battery maintainer on the provided positive and negative posts under the hood, thank you MB, in my 2017 GLE 350 4M. The question is: will this charge both the primary battery AND the auxiliary battery, if that's the correct term? Secondly, does the alternator charge the auxiliary battery directly, or does it somehow pass through the primary battery first ensuring the primary battery gets priority in the event of a weak charge from the alternator? Thank you, Larry.
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From: The Palmetto State
19 E63s, ‘24SQ8, wanting another gas guzzling V8
I thought there was only one large battery for both under the passengers front seat.
I could be wrong though and I have been told before by my wife.
Good luck.
I could be wrong though and I have been told before by my wife.
Good luck.
Out Of Control!!
Joined: Sep 2018
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From: unbegrenzt
2017 GLE350 4MATIC
W166 has a main (starting) battery and an auxiliary battery. For the W166 SUV without air suspension, the aux battery is in the rear right lower cargo area behind trim panels. For other variants it is mounted under the carpet under the rear seat.
Thread Starter
Newbie
Joined: Feb 2021
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2017 GLE 350 4M
I occasionally put a battery maintainer on the provided positive and negative posts under the hood, thank you MB, in my 2017 GLE 350 4M. The question is: will this charge both the primary battery AND the auxiliary battery, if that's the correct term? Secondly, does the alternator charge the auxiliary battery directly, or does it somehow pass through the primary battery first ensuring the primary battery gets priority in the event of a weak charge from the alternator? Thank you, Larry.
One can not charge the auxiliary battery through the main battery but they also stated that the auxiliary battery gets a trickle charge from the alternator once the main battery gets a full charge. Isn't a battery maintainer doing the same thing? Research also stated that the auxiliary can only be charged via a running engine.
I guess I can sleep at nights with that information, but don't be shy about adding a few additional comments to my findings. Thanks, Larry
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Joined: Apr 2016
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From: Southern Illinois
, 2023 BMW X4, 1991 190E
Thanks Scoop7- I have always had questions on the auxiliary battery. I have a 2015 ML with 70,000 plus miles with factory battery which I keep trickle charge. I ve been waiting for the dreaded warning light that the aux battery needs replacing. But I can relax a little now.
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2017 GLE 350 4M
