Adding Aftermarket Amp - Power Source

[ejeffrey]

Hi everyone, new e-tron owner here, 2017 Prestige with sport package. I'm going to be installing a new sound system at some point and I'm having trouble figuring out where to hook up the power wire for the amplifier. This will be a 6-channel amp (4 x 120w + 2 x 230w) with DSP running two-way separates up front and sub.

I've done some research on hybrids and electric vehicles in general, and the consensus is that the best place to get power is at the DC-DC converter before the fuse that goes to the main 12v battery. In our cars the DC-DC converter is in the power electronics and there's no obvious connection point on the power electronics like you would see on a typical Toyota vehicle. I also can't find a wiring diagram of the 12v system.

Does anyone have more detailed info on this?

 

[ejeffrey]

Still looking for info

 

[DrOptiks]

Hi, Try this source - https://cardiagn.com/audi/a3/

 

[ejeffrey]

Hi, Try this source - https://cardiagn.com/audi/a3/

Thank you, this is exactly what I was looking for!

I'm trying to digest the diagrams but if I learn more I will post more info here.

 

[ejeffrey]

After studying the diagrams I found where the power electronics connect to the 12v system. There's two 4ga. cables that are connected to the front of the power electronics near the bottom, a black positive cable on the left (with a brown ground on the right). I believe this is ideally where to connect the amp power wire.

For more context, this wire runs to fuse panel B and connects to the second lug from the left and should have a 400A fuse.

That terminal on the power electronics is not going to be the easiest to get to, but now my concern is powering down the high-voltage system so it's safe to disconnect and reconnect that power wire. Looks like that needs to be done with the service tool.