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I have asked this before, but can't find the other thread. So, bear with me please.
My 2010 E350 has only 51,000 miles on it. About two months ago, got a warning that Aux. Battery needed to be checked (or something like that). Did not say it was dead. Car had been sitting for two weeks or more. Drove it for about a couple of hours over the day and warning has not reappeared. Have noticed that "hill holder"/brake holder at stops does not function anymore. Other than that car drives normally and all systems seem to function.
Car does NOT have stop/start - Thank God.
Plan to have car serviced in Oct./Nov. which is when I usually get it done. Will use same indy that have been using for years. Called them and they estimated $100-200 depending on which battery it actually has - they will get if from MB. Mine is located inside dash on left side. Watched videos - not something I want to attempt.
Does it get recharged by driving as the main battery does?
What is relationship between aux. battery and Sensotronic Brake Control?
If battery totally dies, will I have problems shifting gears?
Any other problems that might be critical?
Thank you!
I have asked this before, but can't find the other thread. So, bear with me please.
My 2010 E350 has only 51,000 miles on it. About two months ago, got a warning that Aux. Battery needed to be checked (or something like that). Did not say it was dead. Car had been sitting for two weeks or more. Drove it for about a couple of hours over the day and warning has not reappeared. Have noticed that "hill holder"/brake holder at stops does not function anymore. Other than that car drives normally and all systems seem to function.
Car does NOT have stop/start - Thank God.
Plan to have car serviced in Oct./Nov. which is when I usually get it done. Will use same indy that have been using for years. Called them and they estimated $100-200 depending on which battery it actually has - they will get if from MB. Mine is located inside dash on left side. Watched videos - not something I want to attempt.
Does it get recharged by driving as the main battery does?
What is relationship between aux. battery and Sensotronic Brake Control?
If battery totally dies, will I have problems shifting gears?
Any other problems that might be critical?
Thank you!
The AUX battery is used to provide backup power to key components like your SBC and the electronic shifter ISM.
The AUX Battery normally gets charged by the car. It can gets drained to supply backup power when the main Batt gets discharged.
Meaning to keep AUX healthy keep up Main Batt voltage when driving and when parked.
A shorted AUX can blow it's charging protection fuse as-in new Aux keeps getting low....
Aux have an easy life: mine is over 12Yrs old.
No mystery: use a CTEK trickle charger or disconnect all batteries when car is not used.
Mine is a 2012 and as far as I can research it has never been changed (doesn’t mean it hasn’t). I plan on putting fresh main, aux, and fob batteries next spring.
I have asked this before, but can't find the other thread. So, bear with me please.
My 2010 E350 has only 51,000 miles on it. About two months ago, got a warning that Aux. Battery needed to be checked (or something like that). Did not say it was dead. Car had been sitting for two weeks or more. Drove it for about a couple of hours over the day and warning has not reappeared. Have noticed that "hill holder"/brake holder at stops does not function anymore. Other than that car drives normally and all systems seem to function.
Car does NOT have stop/start - Thank God.
Plan to have car serviced in Oct./Nov. which is when I usually get it done. Will use same indy that have been using for years. Called them and they estimated $100-200 depending on which battery it actually has - they will get if from MB. Mine is located inside dash on left side. Watched videos - not something I want to attempt.
Does it get recharged by driving as the main battery does?
What is relationship between aux. battery and Sensotronic Brake Control?
If battery totally dies, will I have problems shifting gears?
Any other problems that might be critical?
Thank you!
It appears to be a Mercedes Benz 4039 aux battery.
I recently replaced both original main and 4039 aux on my 2012 GL450 batteries. I decided on a fresh replacement for the original MB 4039 mini aux battery with a Duracell DURA 12-1.3F 12v 1.3Ah AGM mini battery from a Batteries Plus store for $19. Works and fits perfect. I wanted the shorter shelf life of the Duracell replacement over the OEM 4049 batteries available from the MB dealers.
It appears to be a Mercedes Benz 4039 aux battery.
I recently replaced both original main and 4039 aux on my 2012 GL450 batteries. I decided on a fresh replacement for the original MB 4039 mini aux battery with a Duracell DURA 12-1.3F 12v 1.3Ah AGM mini battery from a Batteries Plus store for $19. Works and fits perfect. I wanted the shorter shelf life of the Duracell replacement over the OEM 4049 batteries available from the MB dealers.
Do you see above how the polarities are crossed ?
MB vs. Replacement.
No big deal if you dont reverse polarity upon installing.
Last edited by CaliBenzDriver; Yesterday at 12:05 AM.
You car deserves a new battery to me , having an OEM item still to this day is a huge achievement and definitely ranks up it's reliability record to me as well
2020 RRS superdupercharged 2011c63. 1987 bmw m6. 2018 Audi A6 S-line. (R230SL600 RIP. 500whpDSM4G63
bless your factory aux
[QUOTE=El Cid;9302303]I have asked this before, but can't find the other thread. So, bear with me please.
My 2010 E350 has only 51,000 miles on it. About two months ago, got a warning that Aux. Battery needed to be checked (or something like that). Did not say it was dead. Car had been sitting for two weeks or more. Drove it for about a couple of hours over the day and warning has not reappeared. Have noticed that "hill holder"/brake holder at stops does not function anymore. Other than that car drives normally and all systems seem to function.
Car does NOT have stop/start - Thank God.
Plan to have car serviced in Oct./Nov. which is when I usually get it done. Will use same indy that have been using for years. Called them and they estimated $100-200 depending on which battery it actually has - they will get if from MB. Mine is located inside dash on left side. Watched videos - not something I want to attempt.
Does it get recharged by driving as the main battery does?
What is relationship between aux. battery and Sensotronic Brake Control?
If battery totally dies, will I have problems
I wasted way more time chasing phantoms with an end of life AUX + it made trouble shooting an unrelated issue that popped up far more complicated than it needed to be
Batteries are not immortal, no matter if they're sitting on a shelf, or connected in service with a float charger. If yours is 16 years old, it's way past due for replacement (no law says it has to die before change-out). These SLA batteries are made by many manufacturers, and MB picks one to paste its own price quintupling label on.
Thanks for the replies. Learned last night that the SBC was discontinued in 2006. So that is not a problem.
From what I have seen, my car's battery is much smaller than the one pictured above. Not in trunk, but inside driver's side of dash on the side of it. Have to "pop" a dash panel and then reach inside through bracing to disconnect it and then pull it out. Physically (and mentally) not able to do that. So will get annual service early and let independent do it. They do lots of M-B's and other European cars.
Ironically I also get the indy to replace the main battery. The big auto parts places that replace my Nissan and Toyota batteries will not touch an M-B due to corporate policy.
2020 RRS superdupercharged 2011c63. 1987 bmw m6. 2018 Audi A6 S-line. (R230SL600 RIP. 500whpDSM4G63
Originally Posted by El Cid
Thanks for the replies. Learned last night that the SBC was discontinued in 2006. So that is not a problem.
From what I have seen, my car's battery is much smaller than the one pictured above. Not in trunk, but inside driver's side of dash on the side of it. Have to "pop" a dash panel and then reach inside through bracing to disconnect it and then pull it out. Physically (and mentally) not able to do that. So will get annual service early and let independent do it. They do lots of M-B's and other European cars.
Ironically I also get the indy to replace the main battery. The big auto parts places that replace my Nissan and Toyota batteries will not touch an M-B due to corporate policy.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
) not able to do that. So will get annual service early and let independent do it. They do lots of M-B's and other European cars.
