Aux Battery Malfunction in cold weather
Thread Starter
Junior Member
Joined: Feb 2011
Posts: 18
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e350
Aux Battery Malfunction in cold weather
Haven't seen quite this combination of elements answered in the forums so thought I'd start a new post:
Normally I garage my 2011 E350 (56K miles) but happened to be out of town and parked at a hotel in outdoor/overnight weather that fell to about 25 degrees F. When I started the car the following morning (outside temp was ~ 30 degrees F by that time) I got an "auxiliary battery malfunction" on the dash.
The car performed normally except that the brake HOLD function would not engage.
Later in the day, the HOLD function returned and I have not seen the battery malfunction issue (or any other issue) since I returned home 3 days ago (and back to garaging the car).
I hypothesize this was the in-dash battery. With the heavier winter load on the electrical system still mostly in front of me this season, is it worth replacing presently or could it have just been a anomaly related to the cold? It doesn't seem that if the aux battery dies altogether that it results in an undriveable vehicle.
Thanks.
Normally I garage my 2011 E350 (56K miles) but happened to be out of town and parked at a hotel in outdoor/overnight weather that fell to about 25 degrees F. When I started the car the following morning (outside temp was ~ 30 degrees F by that time) I got an "auxiliary battery malfunction" on the dash.
The car performed normally except that the brake HOLD function would not engage.
Later in the day, the HOLD function returned and I have not seen the battery malfunction issue (or any other issue) since I returned home 3 days ago (and back to garaging the car).
I hypothesize this was the in-dash battery. With the heavier winter load on the electrical system still mostly in front of me this season, is it worth replacing presently or could it have just been a anomaly related to the cold? It doesn't seem that if the aux battery dies altogether that it results in an undriveable vehicle.
Thanks.
Member
Joined: Nov 2016
Posts: 88
Likes: 4
From: YYC
2010 E550 4Matic
It happened to me as well when we had a cold snap (went from 15c to -26c overnight).
I noticed that I had my iPhone charger plugged in the cigarette lighter, which could've caused a small parasitic drain.
Hasn't appeared since.
Just drive it to recharge and all is well.
I noticed that I had my iPhone charger plugged in the cigarette lighter, which could've caused a small parasitic drain.
Hasn't appeared since.
Just drive it to recharge and all is well.
Newbie
Joined: Nov 2020
Posts: 1
Likes: 0
GLK350
Regular occurrence in Canadian winter
I have had my GLK350 for 7 years and I have gotten the auxiliary battery malfunction message everyday throughout past 4+ winters. The car otherwise functions well, so the message is just an annoyance and I ignore it. I prefer to keep my month in my wallet than in the dealer's coffer.
Senior Member
Joined: Aug 2014
Posts: 255
Likes: 36
From: Las Vegas
2012 E350 sedan
Your alert has nothing to do with winter load. Low temperatures decrease the performance of batteries. So the alert is just an indication that your aux battery is aging and not operating at full potential. You can ignore it if you wish but to me it is an early warning that the battery is nearing the end of its useful life. When it happened to me during an unusually cold overnight, I bought a replacement Duracell at Batteries+ which was a fraction of the MB price. Mine is located in the dash which is a more difficult DIY than if it is in the trunk but there are several videos on the internet that can guide you.
