A3 2002 rear speakers not working - which wiring harness needed?


Standard Member
Hi guys,

Was wondering if somebody could help me. I have an ipod interface Alpine headunit installed in my car, (replacing old chorus unit) but the rear speakers don't work, and the unit has to be turned off manually (not by ignition). I think I need a new wiring harness to connect all the cables - will the PC9 401 from autoleads do job? Want to make sure I order the right one!


Thank you


Active Member
The rear speakers are amped which is why they dont work, so yes that is the correct part you'll need. Ignition on/off, and maybe illumination, is controlled by can-bus so you will need to pick up an ignition feed from the fuse box.


Well-known Member
Or you can get a relay if you don't want to run an extra wire. Downside of this is that the stereo will only work when the engine is running.

Just be careful. Even though you have manually turned the HU off it could well be still "powered up" as you have no ignition on feed anymore.


Standard Member
My last battery died so thats probably the reason, ignition wasn't turning the radio off. As for the fuse, does that mean I'll have to replace it in the side panel? I was hoping to attach the harness and hoipe it all works without any additional work

Thank you for the help, much appreciated


Well-known Member
Get yourself down to your local car parts shop and ask them for a relay. It is easier if you don't want to get into the fuse box.

I used a www.incartec.co.uk (part number 10-601). I think it is designed for mobile phone usage but it works just as well with my stereo, (A3 replacement too).

The constant 12v and the ACC 12v are reversed in the Audi too, so you will need to swap the red and yellow around.

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