Question about 2004 Audi A4

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Switchable 12V (with ignition)


I need to locate a switcable 12v supply (for a dvd player) behind the dashboard. I want it switchable with the ignition so that it can;t be left on by mistake (which I did once and ran the battery flat!).

I can't seem to find an easy to get to 12v connection. Any help graetly appreciated.

It's an 04 registered A4 1.8T.



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  • david_lewin Jan 05, 2009


    Many thanks...will try this.




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On the B5 chassis cars (96-01, which I have) there are power posts under the dash on the driver's side. Your car may also have them. Remove the lower dash panel (the one above your legs when you're driving) and look under there. In my car, there are three power posts with red wires running from them, and one with a yellow wire. The yellow one is switched 12v, and I use it to power my XM Radio head unit. The three red ones are constant 12v, which I have used for my phone charger. See if you have these too - if so, use the yellow and you'll be set.

Posted on Jan 03, 2009


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