AMGfan

We have 2 "batteries" in our cars. I got that...one main and an auxillary one. What are the functions of each? I'm mainly confused about the function of the auxillary front battery.

When I'm on a long trip and I get a dead battery from electronic drain from all the electronics on the car (even before I had all the aftermarket stereo stuff in the car)...I've always changed the main battery (3rd time for me). I've gotten to the point where I upgraded the battery and bought a CTEK battery charger so I'm covered with regard to the main battery.

I'm assuming the auxillary battery isn't affected by the "electronics drain" of the car and shouldn't worry about it...but that is my assumption with no real knowledge to back it up.

Should I worry about it? Do I need to "maintain" that aux battery while I'm away on a long trip? Thanks ahead of time for the 411 from my fellow Beast brothers...

J

PS...I'd look in my owners manual but for some reason I can't find the damn thing...

chiromikey

iirc, the aux battery makes sure the sbc system always has power. and i also seem to recall that the ecu will throw battery codes for that one since it monitors it a bit more stringently than the main battery.

if that's not correct, someone around here will know and help out.

AMGfan

From what I remember from the last battery failure I had...the convenience features shutdown, then the red error code came up stating impending brake failure. A minute or so later, I lost all power to brakes and steering and it felt like I had a brick under the brake pedal....

So did the aux battery also lose functionality, too?

On a tangential note...while looking up SBC on the internet...I found this tool for DIY's who work on their own breaks...

http://www.do-it-auto.eu/product_inf...delle-W21.html

BENZGal

Yes, the aux battery shuts down first from what I was told. I had a similar problem and feel your pain. I never had the brakes shut down. Yikes! I highly doubt it is your after market system. PM sent