Battery drain with ignition on

B6/7 S4/RS4
#1

Posted this elsewhere, but still cant find out what the acceptable current should be!

Anyone know what the current draw should be with the ignition on, engine off, and radio, heater etc turned off? S4 B7 by the way.

The RNSE radio will draw 3A even when off (until it sleeps), but I’m drawing 9A with the ignition on.

I’ve pulled every fuse in the drivers fuse box one by one, and there’s nothing that flags up as high current draw. So what the hell could be drawing 5A, and is that normal, as 9A total just seems very high to me?

#2

That seems to be a lot. I can go measure but I know there is going to be some draw as some systems require constant feed to keep data correct. But 9 seems a bit much.

There could be a break in the wireharnes that is causing part of the issue. The entire passenger side wire harness becomes brittle and the actual wire covering starts to break off.

#3

Well if you can, that would be great!

I only noticed it when doing a JHM ecu and tcu remap, and had to go and buy a 20A charger just to keep the battery at a constant voltage lol. Decided to measure the current, and boom, 9A.

The steering wheel electrics seem to draw 1A, and the radio 3A, and all the other fuses were negligible, so I guess its actually 4A total draw unaccounted for. If other people’s are 9A, then I’ll leave it, but I’d be surprised if thats normal lol.

Are there any other fuses in the engine bay etc, or are they all just relays? Cant find any info anywhere.

Thanks again mate, its always nice to get help from someone who actually knows what he’s talking about :slight_smile: