If message flashes saying Auxiliary Battery Malfunction , Should I show the car to the dealer as it is still under warranty ?

I would. Better safe than sorry.

It flashed only once so far I.e yesterday.I ran the car 20KM today and there was no more this message.I am a little reluctant to rush to the service centre as it is quite far and I am quite old

Thanks.That is very reassuring.I shall wait at least until the same message flashes again

The battery apparently ran down - that is why the error. Your driving it got it recharged. That would indicate that the charging system is working. Have the battery checked to make sure it is holding a charge - you would be checking for a weak or malfunctioning cell.

Thanks.I shall be on the lookout for any further message

My E class e220 14Reg.It flashed Auxiliary battery malfunction since yesterday continues when I start every time flashed

We have a S 550 on which we had the auxiliary battery replaced Monday and it failed again this morning. (Thursday) Any ideas?

C200 2015 keeps flashing this message. garage saysbitnis OK to drive until they can fix it 11th September. I am not aware of having run down the battery, so why is it malfunctioning?

Take it to the dealer now. The Auxiliary battery controls many of the functions on the car. The main battery is for starting only.

Thanks bobkat. MB was not very informative. They said to drive the car as usual. If i break down, breakdown services will just fix the problem. I prefer not to beak down though!

I have CLASS E350 2013 WITH 16000 MILES, i NEED TO REPLACE MY AUXILLARY BATTERY . IS IT STILL UNDER WARRANTY

At the dealership now. They recommend replacing my battery (GLK350) at the tune of $250.

I have noticed that, if the message appeared, the hold parking future will not working. also, on my E200 if I turn on the key while I'm pushing the key the message appears , but if I was pulling the key while I turn on the car the message didn't appeared.

I have E 350 year 2010, about 76000 miles, it show on screen says Alkaline battery malfunction, what is that mean, should I take to dealer to check

Mercedes have two batteries. The primary battery and the auxiliary battery. The auxiliary battery is used to help run your cars accessories. It is rare that the car will not run, so you should be able to drive it normally, but some accessory functions may not work.

In addition of GuruXSDRN answer It is for car memori and breakhold option

I have a 2016 E350. My Auxillary mal warning has been on for more than 6mons Everything in my car is working and I have no problems. I just ordered the battery online cheaper than the dealership just in case but like I said everything is working fine.

Is it safe to drive my c220 mercedes if the sign comes up auxillery battery malfunction keeps showing

In my case, I think this MAY have happened because I broke my ankle and haven't driven the car in several weeks. Mercedes told me the more I drive, the better; the battery will recharge.'

Hi there. Is there a reset button to be pushed after an auxiliary battery replacement on a 2018 Metris? Thanks.

Just drive the car, the more often you drive it will help recharge the auxiliary battery.

Where do I find the auxiliary battery in a 2015 c250 mercedes.

They don't make Mercedes the way they used to. My C300 is little more than 4 years old and just out of warranty. Even though have owned Merc since 1983, am quite reluctant to buy one in the future. My 9 yr old Lexus show no such signs. So, for me Lexus might be the way to go.

Where do I find the auxillarybatery in a 2012 ml 250 blutec

Yes should show the car to the dealer if it is still under warranty. I also faced similar issue just a week ago but unfortunately my car was out of warranty. I found an other auxiliary batter replacement part from a online store and replaced it by myself with the help guide given on this website. https://xenons4u.co.uk/blog/mercedes-benz-auxiliary-battery-malfunction- explained/

So my Auxiliary battery malfunction light only comes on if I dont drive it for days. After driving it for an hour or so it goes off and stays off until it sit for days again. Is something killing it? I had my scheduled maintenance and MB said not to worry I won't get stranded but it would be $250-$300 for a new battery. Getting a new battery and something still draining it is a money waster.

I went and spent $1900 for b service including getting a brand new battery and something else per dealership recommendation 4 months later the check engine line came on and once came a message saying auxiliary battery malfunction... live the car but it’s ridiculous ... dealership statuses it cost $400-$450 for ab?? What is it made of gold?? Should have kept my Lexus!! No problems at all

*love car only has 56k miles 2011 My Lexus has 70k miles and never had an issue at all and that’s a low maintenance car.... I hardly drive this car. When I called the dealership they said it’s got some age... rally because it’s 2011? Really ? But it only has 56k miles .... driven very seldom...

I had my car sitted for 3 weeks and on first of my ride I saw a message of auxillary battery malfunction shall I wait couple of days or miles to get recharged or there is problem in second battery? Pls let me know problem thanks.

My w212 2014 Aux battery is in the trunk next to adblue tank, you have to remove the material cover on the right hand side floor to expose the battery. This model is not in the dash as some people have mentioned, the dash (console) model is a much smaller battery.

Aux battery is a back up power source of the main battery for safety related functions. For example, power to brake system, airbag, etc. When a car sits for a while, any battery will self discharge a bit. A partially worn out aux battery will self discharge so it becomes low in voltage, thus triggering the error message. Once the car is started, the alternator first charges the main battery for the power lost during sitting, and those used by the started. After the main battery reaches its maximum, the aux battery gets electricity to charge it up. If you aux battery is flashing message intermittently, you may want to check your main battery condition first. As a weak main battery can prevent the aux battery from being charged unless one goes for a long drive so the main battery can be fully charged up. It happen to me once as I have replaced the aux battery only about two years when the red message flashes from time to time. After replacing the main battery but not the aux. battery, the red message has been gone for years and the car is now 14 years old.

I had mine changes after the warning light came on four times in two months. Cost for my E400 was $345

I'm the 3rd purchaser of a 2016 Mercedes-Benz E350 Sedan with 93,000 miles on it and I've just noticed the Auxilary Battery failure message starting to be displayed. It may control other features but the only noticeable feature that stopped working was the DISTRONIC PLUS system which also governs cruise control and adaptive cruise control. As for the main driving functions of the vehicle, the critical functions, are on the main battery and you can drive the car. In my case, there are no error messages caused by the failure message, none under services messages and none that are found with the service port on the vehicle so in my case it's also intermittent. It's possible that it's the voltage regulator (a capacitor type device) Here is a URL that addresses it somewhat: https://xenons4u.co.uk/blog/mercedes-benz- auxiliary-battery-malfunction-explained/. Please bear in mind this does not address all vehicles as some Mercedes, as mine does, puts the auxiliary battery in the trunk area and not in the passenger compartment, as shown at this website. As for the battery that Mercedes uses it should only cost around $84.00 for the battery itself and I don't know the cost of the regulator device but I would guess somewhere between $25-$35. With Mercedes, though you have the OEM part markup and huge labor cost hey if you choose to drive the best you accept some things that come with it such as using premium fuel only and paying a premium price for a vehicle that performs among the best of them.

Could not find any info on the aux battery in the owner's manual ? for my 2017 E300. Drive my car every day so, don't see how it could be discharged. Maybe answer above that suggests that main batt is charged before the aux gets any recharge is correct explanation. but still mysterious. Everything too expensive from dealers!

bobkat answered 2 years ago Take it to the dealer now. The Auxiliary battery controls many of the functions on the car. The main battery is for starting only. Actually is the other way around. The main battery controls most of the functions while the aux battery's main function is stop/start service. Aux battery is acting more like a backup.

So it is safe to go for a long drive of 4 hours to and from if the auxiliary battery is dead?

I have a MB 550Sl with 4,000 miles. I recently got a warning that said Auxiliary Battery Malfunction. The car battery was replaced a few months ago. What is the auxiliary battery? What should a MB dealer cost to repair be? Do I need the MB dealer replace the AB or can a can mechanic do it? Thanks