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When should one replace auxilliary battery? Where is it?
My 2016 E350 is ~10 years old, and just hit 100K miles.
Should I replace the aux battery?
Main batteries usually last about 4 years...what's the typical lifespan for aux battery?
Also where is it located?
Some said it's in the trunk/boot, but others said it's in the side panel of driver seat.
I don't have the "Auxiliary Battery Malfunction" error.
I did receive "collision prevention assist plus inoperative" error, but it only appeared once two weeks ago, and hasn't shown up since then.
The ECO start/stop function sometimes works, and other times doesn't...it's not very predictable.
I rarely use the HOLD function, so no idea if it works consistently.
My 2014 E350 Aux battery is located in the trunk. It is really easy to check. I noticed the error a couple of months ago and replaced it myself. It was an easy job. I would just wait until you get the error message before replacing it.
I'm not aware of any battery with an unlimited life, regardless of how it's treated. Aux batteries that I'm familiar with are sealed lead acid (SLA) types, the same technology used in devices such as UPS (uninterruptible power supply) applications, where they are on constant float charge except when serving their purpose. In my experience, SLAs can last 5 to 10 years depending on how they're used. Your aux battery might not be SLA, but whatever its type, it's unlikely to last forever.
Being a 2016 model year, it should be at the trunk, besides the mini spare tyre.
Go and find it.
2018 archive
If you can't find it, yours maybe the latest version without actual battery, but an anti-voltage-dip capacitor system.
I do not know where such capacitor system is located.
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While at it, check your mini spare tire valve by pulling-shaking it hard, it would likely be rotten already from aging.
Mine and Cali's rotted by 8th year.
Confirmed the aux battery is in my 2016 E's trunk as well, right next to the spare.
I've taken the spare out due to a flat before; funny I didn't even notice it's there the whole time.
or maybe I did see it, but just couldn't remember it, due to multiple cars we have.
Good news is it doesn't look hard to replace, when the time comes.
I was very worried it was located in the side panel...when I replaced the cabin air filter on the passenger side, I was really struggling to access it, due to its ridiculous location, and I was afraid it was going to be the same deal for the battery.
thx for pointing that out
I'm pretty sure my main battery is also vented w/ a tube connected on the side, so will make sure to re-connect it after swapping out the battery
thx for pointing that out
I'm pretty sure my main battery is also vented w/ a tube connected on the side, so will make sure to re-connect it after swapping out the battery
yes indeed.
Don:t buy the wrong ATV battery
your vehicle requires a vent port.
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When should one replace auxilliary battery? Where is it?
