Auxillary Battery
Thread Starter
MBWorld Fanatic!
Joined: Nov 2009
Posts: 2,616
Likes: 160
From: Southeastern USA
2010 E350 Luxury Sedan, Engine 272 (V6)
Auxillary Battery
After 15 years, my Auxiliary Battery malfunction light came on. Called the indy who does my work and they have to see it and then order the battery and takes 1-2 days depending on when they get it. Probably from the M-B dealer in next county.
Costs either $100 or $200 depending on battery.
How long can I drive the car with the warning on?
Thanks!
Costs either $100 or $200 depending on battery.
How long can I drive the car with the warning on?
Thanks!
Out Of Control!!
Joined: Apr 2019
Posts: 11,921
Likes: 6,769
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Out Of Commission
After 15 years, my Auxiliary Battery malfunction light came on. Called the indy who does my work and they have to see it and then order the battery and takes 1-2 days depending on when they get it. Probably from the M-B dealer in next county.
Costs either $100 or $200 depending on battery.
How long can I drive the car with the warning on?
Thanks!
Costs either $100 or $200 depending on battery.
How long can I drive the car with the warning on?
Thanks!
At 15Yrs, it's not worth splitting hair with reconditioning charge.
Its normal for AUX to loose charge when Main drains out. This may still happen with a new AUX then you can use counter measures: CTEK float charge!!
MBWorld Fanatic!
Joined: May 2021
Posts: 2,524
Likes: 2,041
From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Last edited by JCM_MB; Jan 20, 2026 at 09:02 PM.
MBWorld Fanatic!
Joined: Dec 2011
Posts: 4,372
Likes: 945
W212 FL
Nice to see long time member 
Well, I was not aware of a warning light for the Aux Battery to be honest. Different things but battery related , I could be able to drive my key fob with a warning low battery message more than 4 weeks
Well, I was not aware of a warning light for the Aux Battery to be honest. Different things but battery related , I could be able to drive my key fob with a warning low battery message more than 4 weeks
Thread Starter
MBWorld Fanatic!
Joined: Nov 2009
Posts: 2,616
Likes: 160
From: Southeastern USA
2010 E350 Luxury Sedan, Engine 272 (V6)
Thanks to all!
Ironically I had not driven car in about a week when got notification. Drove it about 20 miles and notification did not come back next times started up. Replaced main battery in Nov. 2021. Will get it checked. I can get that done at Advanced or AutoZone, but they will not install a new one - company policy. Fortunately the indy can do it.
Was told years ago by M-B service manager that need to drive car 20 miles or more to charge main battery. Car has to be moving to charge battery.
Watched a video on changing Aux battery on 2010 M-B E350. Not something I want to do.
Ironically I had not driven car in about a week when got notification. Drove it about 20 miles and notification did not come back next times started up. Replaced main battery in Nov. 2021. Will get it checked. I can get that done at Advanced or AutoZone, but they will not install a new one - company policy. Fortunately the indy can do it.
Was told years ago by M-B service manager that need to drive car 20 miles or more to charge main battery. Car has to be moving to charge battery.
Watched a video on changing Aux battery on 2010 M-B E350. Not something I want to do.
Member
Joined: Dec 2022
Posts: 87
Likes: 34
From: Slovakia
2011 E350 CDI 4Matic, Rover 75, Chevy K2500, 2 motorcycles
Thanks to all!
Ironically I had not driven car in about a week when got notification. Drove it about 20 miles and notification did not come back next times started up. Replaced main battery in Nov. 2021. Will get it checked. I can get that done at Advanced or AutoZone, but they will not install a new one - company policy. Fortunately the indy can do it.
Was told years ago by M-B service manager that need to drive car 20 miles or more to charge main battery. Car has to be moving to charge battery.
Watched a video on changing Aux battery on 2010 M-B E350. Not something I want to do.
Ironically I had not driven car in about a week when got notification. Drove it about 20 miles and notification did not come back next times started up. Replaced main battery in Nov. 2021. Will get it checked. I can get that done at Advanced or AutoZone, but they will not install a new one - company policy. Fortunately the indy can do it.
Was told years ago by M-B service manager that need to drive car 20 miles or more to charge main battery. Car has to be moving to charge battery.
Watched a video on changing Aux battery on 2010 M-B E350. Not something I want to do.
