Audi A3 (8L) Radio Wiring Diagram?

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Tooks

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Hello, does anybody have/could point me to a wiring diagram for the A3 (8L) radio wiring loom?

I'm in the middle of putting the bits together to change my standard Concert head unit to a Becker Traffic Pro.

I'm ok with the speaker plug, and I've got an adaptor to take care of the active rear speaker issue. (Autolead PC9-401).

On the plug from the car which contains the power feed, I've only got four wires. Using my multimeter, I've sorted the Power, Earth and IGN, but there is another wire which doesn't seem to do anything. I thought it was the illumination feed, but the voltage doesn't change when the lights are turned on. Maybe it's the GALA signal? My car is a 2002 MY, so is this one of the part CAN-BUS cars?

I've had to move the wires around on the Autoleads adaptor in order to get the Power/Earth etc to the right plug on the radio, which I thought was strange, but at least I've not had to chop the car wiring. On the adaptor, I've also got the blue and white wire which isn't connected to anything at the moment!

Anyway, thanks in advance for any help/pointers, but I've read searched posts to death and seem no nearer sorting it out! I appreciate it's very difficult trying to help somebody over the internet when you really need to see the wiring, but hence my hope for a wiring diagram!
 
does it give a +12v when the head unit is switched on? If so it could be for the automatic antenna/booster?
 
Hi, thanks both.

Good call re the sticker - sometimes you can't see the wood for the trees!!

Anyway, according to that, the four wires I've been talking about are 12v Permanent, Earth, DWA-GND and K-Bus... The last one is the one that I thought was 12v IGN.

What are those last two wires? I guess it confirms the car is CAN-BUS so probably looking at a whole heap of trouble!

The 3rd connector to the radio (the one that powers the rear amp/speakers), also has a Switched 12v, COM, CAN-L and CAN-H.

I suppose I can still re-rig the autoleads connector to give me all of the connections I need for the becker, and without cutting the car wiring, as all that needs is Permanent Positive, Switched Positive, Earth and Illumination. I can run a wire for illumination easily enough, but would this be asking for trouble with a CAN-BUS car?
 
The only issue on a CANBUS car is the switched live as there isn't one. So you either wire one in from the fusebox or you pair the perm & switched lives together and turn the HU on/off manually.
 
K-bus is the diagnostic line, as Andy says, get a switched live and possibly a lights feed elsewhere. Or buy a can converter that will generate all these signals from the can wires.
 
I've been going through similar problems with the install of a Becker Cascade 7944 into my 2006 A4 cab, I bought the canbus interface from low cost audio that you linked to and that semms to sort out the live supply issues.

Your comments above indicate to me that I need an interface to connect my speakers and probably explains why sound only comes out through the dash mounted speaker at the moment.:keule:

The canbus is supposed to give steering wheel control but mine doesn't work but that may be related to the speaker issue.

Oh and I cannot tume the radio, another lead to buy...
 
You need an antenna amplifier to get the radio to work
You need one of 2 adapter leads to allow the new HU to plug into the active speaker system. I take it you have the Bose system upgrade if none of the speakers work?
 
Rhinoman, as Andymac says, you need a powered aerial adaptor too. My radio would only pick up Saga FM before that! With the adaptor though, it picks up everything.

According to my local ICE shop, I would still need the autoleads active rear speaker adaptor as well as the CANBUS adaptor for everything to work as it should... That's £160 pounds worth of connectors!

Can I ask, did the CANBUS connector get you the speed sensor output for your Becker? I haven't connected a speedo output yet, and it won't seem to calibrate without it connected?

I've located the speedometer outputs on the back of the dash module, so I'm going to try tapping into one of those and running it to the appropriate connector on the radio.

I'll get that done tomorrow, so I'll let you know if it works or not.
 
Thanks for the replys chaps,

A active aerial connection it is then.#

You need one of 2 adapter leads to allow the new HU to plug into the active speaker system. I take it you have the Bose system upgrade if none of the speakers work?
Click to expand...

No its not bose (I think, bit of an arguement going on here with the supplying contract hire company) but it definitly is amped, the iso connection only has "front" connections and that seems to feed just the dash speaker, the line out connector block that also takes the canbus and cd interface has connectors for FL, FR, RL, RR and also a switched supply and common pin, I'm guessing the switched supply feeds power to the amp/s(?). I'm now not sure if I need the PC9-401 or just need to supply the amp with Volts, only issue is the concert2 that is coming out only puts 9.75volts on the switched supply, if I took an ignition live that would be a bit high?

I've found out why the steering wheel controls didn't work, the canbus adapter share the same space as the Becker ipod interface plug, swop them over and the steering controls work fine, I just need to merge the plugs, can anyone recommend a tool for extracting the pins from a plug?

The other issue is that the plugs both have the same pins used so I guess a call to Becker tomorrow might be in order to see if that will cause a problem in using the ones from the canbus interface.

Tooks
Can I ask, did the CANBUS connector get you the speed sensor output for your Becker? I haven't connected a speedo output yet, and it won't seem to calibrate without it connected?
Click to expand...

It does provide a speedo connection as well as a reversing output (mutes the cascade when you stick the car in reverse, useful for the wimpy volume of the audi parking sensors).
 
All Audi HU's have both front and rear pre-outs, but the fronts are only used on the Bose upgraded system, non Bose systems have the front speakers and centre speaker (which should be disconnected as it's hideous) directly connected to the HU's internal amp.
No idea why your's seems to be different but pretty unlikely they changed this format just for the cabrio as this is the setup on all Audi's for at least the last 10 years.
The switched supply on the pre-out/CANBUS connector is the remote on for the Audi amp, this simply provides a low current 12v to the amps relay to switch it on and off with the HU.
you need to get an adapter to feed the rear pre-outs (RCA) from the new HU to the above connector as it needs both the switched supply and the pre-outs in order to work.
 
All Audi HU's have both front and rear pre-outs, but the fronts are only used on the Bose upgraded system, non Bose systems have the front speakers and centre speaker (which should be disconnected as it's hideous) directly connected to the HU's internal amp. So the standard speaker harness should have the 4 middle pins wired along with 2 skinny wires bridged across the front left/right wires for the centre speaker.
No idea why your's seems to be different but pretty unlikely they changed this format just for the cabrio as this is the setup on all Audi's for at least the last 10 years.
The switched supply on the pre-out/CANBUS connector is the remote on for the Audi amp, this simply provides a low current 12v to the amps relay to switch it on and off with the HU.
you need to get an adapter to feed the rear pre-outs (RCA) from the new HU to the above connector as it needs both the switched supply and the pre-outs in order to work.
 
Hi Andy,

thanks for that but just to confirm, the canbus interface comes with a plug to pass through the preouts from the becker, its only the switched supply thats wrong so couldn't I just use a switched 12v to turn on the amp?
 
Don't see how it can do that without including the remote on, but yes if it doesn't include the remote on then just use the remote on from the Becker and piggyback it onto the correct wire on the Audi loom
 
It has got all the connectors, its the Becker headunit that doesn't use the same pin for remote on, its a sub out on the Becker.

I'll give it a go and see.
 
Just an update, and further question really!

I wired the speedo output from Pin 31 of the blue 32 pin connector at the rear of the instrument cluster, and now the Gala and Wheel Sensor connections on the radio work fine. The sat nav calibrated within a few hundred metres once that was connected. I also ran the illumination wire from the cigarette lighter, which again is fine.

Now the question. I struggled to find an easily accessible switched ign wire, but seeing as the K-Bus wire on the head unit loom puts out 12v when the ignition is on, and zero when it's off, I've used that. I did orginally splice the permanent 12v on my adaptor loom, but that meant I had to manually turn the radio off, and when I removed the radio face, the cd illumination lights were still on. I was concerned about draining the battery etc as I suspect the GPS receiver was still powered up too. Now, when I remove the ignition key, the radio powers down too, just like the factory unit did.

So, the K-Bus wire seems to act to all intents and purposes like a switched 12v supply.

I've read about the K-Line issues on Vag Com with aftermarket radios, but as I understand it this is only an issue when the radio is putting 12v back in to the loom (ie wired up incorrectly)? The pin I've connected it to on the radio is a 'dumb' pin, and definately only receives current. I've also measured the voltage across the pins on my diagnostic port, and they are within tolerance.

Any problems anybody can see with what I've done?
 
Tooks,

I won't answer the technical side of your qustion but I'm glad to see you have it working.

I've had a bit of sucess, I took the C6 pin from the preout section of the becker which is the live switched supply pin from the concert2 andd took it across to the ignition live on the iso connection from the canbu interface. I now have working speakers via the beckers preouts and the audi amplifier.:cool:

I called Becker uk about the steering whell controls sharing the same pins as 2 of the pins on the ipod interface and they didn't have a clue as they dont make the ipod interface, its made for them:think:

I got hold of soundlinx who make a BEC01ADP which is a Y adapter for the plugs in question, having bought it and fitted it it appears the ipod takes presidnce and the steering wheeel controls dont work.... I'm hoing to try taking the 2 pins from the ipod interface next and see if it still works.
 
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