Please Need help with wiring new aftermarket headunit


Registered User
Hey guys hope you all fine . So I decided to upgrade my factory cassette head unit to aftermarket Kenwood single din everthing is fine just after all the harness plug in the rear speakers not working only front is any one have same problem and solve it .. so in the pics you can factory one have 6 wires going into 4 and this IOS connector have 8 wires for all speakers i have no idea what to do to make rear one working .. please help


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Registered User
No no that is no for aftermarket head unit . This connect in factory headunit .. aftermarket head unit only need to connector one for power one for speakers

I'm Just Rob.

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Are you just trying to fit the aftermarket HU to the existing audi loom or did you invest the correct wiring kit that does all the wiring conversions etc.


Registered User
Depends which sound system is fitted to the car as standard.

In my B7 the Rear speakers are controlled via the subwoofer unit located in the right hand side of the boot space. So the signals sent from an aftermarket head unit are interrupted and are much lower output - you can get around this by increasing the fader to the rear on the head unit, but it’s not going to sound as good as the factory system.