TheVazha

Hello,

I was unclear about the AUX battery in the engine bay and so I thought I'd share this. It's not rocket science but I would have like'd to see it. Anyways, a local shop tried to charge me $50 to install the thing. I'm sure it's less then the dealer but for the money I saved I bought some new white Chucks.

The battery cost $100, and I think you can get it for less but I thought it was a good deal for an OEM part, NIB.

Hope this helps someone!









Super easy, 9 min tops for the swap.

speedpeddler

Please tell me you have more than one tool and don't perform all your mechanics with a pair of needle nose plyers.

Right tool for the job ya know?

moosejaw

LOL.....
I did this in about 5 minutes with a 10mm socket.
I spent more time prepping the battery. That info should be posted here as well.
I spent $80 on my 14BS Motorcycle battery which included a $15 core charge at WalMart

V12Godspeed

Were you getting any error messages that prompted you to change the battery? I am getting a message that states " Battery protection Conven. functions temporarily Unavailable". Something tells me the little Aux battery is going...

Thanks.

novae500

yes thats one of the signs that the aux battery is going. For me i bought a battery charger CTEK instead of buying a new battery

outrun

sub.t for future use.

Hotrod-Realtor

You guys rock. It took me 20 minutes using my wife's salad tongs.

J/K of course.
As a former Snap-On tool salesman, the photo with the cheap needle nose made me cringe. I feel a little guilty busting on you, the vazha, all in fun though.

abhatti55

Replaced my aux battery this past weekend as well. Just my luck, it was my battery control module that was bad. It has been updated 6 times, 4 times since my part number. Hopefully they got it right this time.

nanayaw6

So, is the aux battery used for electrical consumers or is it used to crank the motor when the main battery in the trunk dies off?

Toadster

the MB SA told me that the computer needs reprogrammed after changing this out - true?

was saying $340 to swap the battery and program... I was like wtf?

Ronan Mc Cabe

My Indy did it for $150 (inc. battery). Don't know if any reprogramming was necessary.

moosejaw

Sounds like your talking about main battery?
Even so..no reporgramming is needed

I recently disconnected my battery and had to turn the wheel side to side fully locked to get rid of the ABS,ESP, and Headlights Inoperable Message. Also had to reset the windows and sunroof

Do not have the dealer do any battery replacement. Your SA is outright lying to you.
MB Breakdown assist can replace the main battery for $180 at your house!
The Aux Battery is a 14BS unit sold at WalMart for $80. Ive had mine for two years no issues.

cij911

This is very true unfortunately...The computer needs to have the ball bearings greased to withstand the mega volts coming from the new battery...Sometimes, the dealer needs to change the mouse in the alternator too because it is tired....

I sure hope you kicked the SA in the sack....

justinwrock

Maybe to clear codes from a low voltage condition?

moosejaw

Perhaps to reflash the ECU back to stock?

Can you imagine what Toadster must put his SA through? Must be a real interesting convo.
I bet you his SA put a transponder on his car so they get notice before he comes in. That way they enough time to bolt out to lunch.

Toadster

very cool - I see at Sam's Club

Model: Group Size 14BS
Item #:118643
Energizer AGM PowerSport batteries are designed to power all of your motorcycle, ATV, scooter, personal watercraft and utility vehicle needs.

Only $73 - I figured it's a simple swap and the SA said it was a 'special MB battery part' - yah, I'm a new MB customer but I wasn't born yesterday either

moosejaw

Thats it dude

vietjdmboi

Got mine thru advance auto for $51.xx using their online coupon code.

Alps

straight forward swap, this was causing my ECU to stop updatdating during my EC flash.

note:- battery is on the other side for RHD cars

novae500

last few weeks got the Convenience functions disabled, low battery. This morning Visit workshop battery icon. Main battery i replaced last winter so should be good to go. But will check the voltage on both as well as the alternator. Hopefully its just the auxillary battery. But i also bought a voltage regulator to replace as well.

Ryououki

Had to replace both the AUX and Main batteries this past weekend. Easy enough and thankfully no more errors.

novae500

Well installed new aux battery and still red battery light . Volts car off 12.8and when running idle 13.5. Next is to do the voltage regulator and see if this will ge rid of red battery light . Debating if I should drive to autozone to get alternator checked

moosejaw

Might be main battery?

AMG903L

I just ordered both batteries and a voltage regulator hope this will cure my errors.

Main: Braille Endurance B10049

Backup: Braille No-Weight B14115

VR: Huco W0133-1852913

Does anyone have a write up on everything that will need to be recalibrated and how?

Steering Wheel
Windows
Sun Roof
Trunk
???

novae500

Steering all the way left then right . Windows once at up position lift up on the window tab and hear a click hold for 3 sec. Do for each window . Sunroof pull tab down to hear click and hold 3sec should be good to go