karan khaneja

Hi Guys,

This is my first thread so hello everybody!

I have a audi a6 (c8) black edition 45 tfsi with the tech pack, comfort & sound pack.

However for my taste the bass is slacking. For some it will be more than enough.

I am currently trying to do a Sub & Amp install but Im having difficulties finding the 2nd battery (if there is one)

Ive located the 12v battery in the engine bay which leads to a connection point.

However there is a 0 gauge power cable going through the firewall which leads me to believe there is a second battery.

Can please someone explain the battery system in the a6. I’m not sure if i can power the amp with the 12v in the front, i believe it is for the mild hybrid system.

Also, where is the 2nd battery?

Thanks guys

doctorharrison

In the 2019 A7, there is a battery located in the trunk passenger side sidewall, and easy to remove the access panel with a plastic pry tool.

gk1

Interesting. Where is the battery in the engine bay? pic?

angrypengu

The 12V battery is either in the engine bay or as doctorharrison pointed out, -there.

The 48V battery is located underneath the trunk floor. Don't touch it, don't even look at it. :P

Silver42

yes - any connection you make with the 48V battery (to provide services for the mild hybrid system....) will blow fuses and maybe your amp. See the post above don't even look at it and DO NOT touch it. you will have to run a heavy RED cable from the 12V battery under the hood (FUSED) to the rear for the amp. you can then ground out the amp to somewhere local in the trunk.

karan khaneja

Hello again,

I managed to find the 2nd battery and surprisingly it also says 12 volt on the battery.

Done the connections to the amp & it is switching on fine with no problems as it’s a 12 volt.

Picture of the battery is attached.

In my car it was in the boot on the right side.

My car is a UK a6 black edition 45 tfsi.

rear battery

Battery in engine bay

gk1

The rear one looks like the battery. Clearly marked AGM on it too. Also you can see the tail end of "varta".
The front looks like a connection point or regulator of some sort. Encased in aluminum.
It would be really weird to have two 12v batteries if one would do

karan khaneja

I think you are right 👍

Thanks for the help guys anyway