Need help wiring aftermarket headunit to 2010 8P A3

AK47UK

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I am in need of some advice. I am researching too but thought I would post here in the meantime as it should be fairly easy.

Due to lack of funds (and decent past experience with Xtrons), I opted for a clone of the Xtrons PF71A3A. It was touted to support Bose and as it was designed for the A3 I thought installation would be easy. I had read of others having problems but that was some time ago and this came with 2 ISO harnesses so I thought that must have been resolved, it appears I was wrong...

My car uses the quadlock, here is an image from another thread, mine is the same except it is missing the yellow/orange connector:
Audi5.jpg


Now the adapter that came with the HU looks like this:
XtronsConnector.jpeg


Note the green and blue plugs have nothing to connect to! I imagine they must do some pretty important stuff... There is also 1 pin on the black section missing from the harness.

I have 3 spare wires on the harness labelled:
GND
KEY1
PANT

I imagine the ground is supposed to be for the handbrake so video cannot be played whilst the car is in motion, where am I best wiring this to? And where do the other two cables go?

I am fairly good at wiring but don't want to cut or change the OEM cabling, I'd rather buy another harness and adapt that so if I wanted to I could go back to stock.

Also the radio cable in my car is a double but the radio antenna ISO adapter only has a single connection, does it matter which I use? Is one just an amplifier or digital radio?

Just teething problems and also I am sure you all know the best places for earthing etc. I could find one myself but would rather listen to experienced A3 owners ;)

Thanks

P.S. Is there a wiring diagram for the quadlock anywhere so I can work out what each pin goes to myself?
 
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might be an idea finding out what the blue and green quadlock leads do before chopping them up

blue one is for cd changer
green one is for remote control

the 3 spare wires are

1. ground ... could possibly be the bose pin or main ground
2. key 1 is for a wired remote ..like steering wheel controls
3. pant is power antennae not many cars have these nowadays but older classic cars will
 
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might be an idea finding out what the blue and green quadlock leads do before chopping them up

blue one is for cd changer
green one is for remote control

the 3 spare wires are

1. ground ... could possibly be the bose pin or main ground
2. key 1 is for a wired remote ..like steering wheel controls
3. pant is power antennae not many cars have these nowadays but older classic cars will

I wasn't going to chop up my audi harness mate, want everything I do to be easily reversible. Thanks for the info, so the blue block is useless to me as I don't think I have a cd changer and I don't listen to CDs but the green is important as I have steering wheel controls.

I m concerned about the supplied harness having a lot of connections for the missing yellow/orange block on my audi quad lock connection. I've tried to find the pin diagram for the Bose system but can't find it anywhere! With that I could work out what needs wiring to what, it looks like I should have been sent a further cable which connects to the bottom section of the audi quad lock and it has RCA cables coming from it, I assume this must connect to the av output from the HU...

with thy the missing cable I might be sorted but the supplier hasn't got back to me yet. If anyone knows how the Bose is wired up and which pins are which it's be a huge help ;)

Thanks again :)
 
I've been thinking about this and looking at the photos of my HU online and I am missing a cable that would connect to the blue/green blocks of the quad lock and would have RCA type connections coming out. Would I be right in assuming the green or blue block send the audio signal to the Bose amp and perhaps the remote wire to the amp too so it knows wen to turn on?

i guess I need this cable from the manufacturer and then connect my RCA out from the HU to this cable so my amp gets the audio feed, then I might be there. Possible need an induction loop if the speakers pop when powered on...

if anyone can help me decrypt the pin out I would appreciate it, want to sort this ASAP so I can get on with enjoying the car :D
 
yellow connection has all the rca outputs on

pin 1 line out left rear
pin 2 line out right rear
pin 3 line out common ground
pin 4 line out left front
pin 5 line out right front
pin 6 +12v switched output
 
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Seeing as the yellow connection is missing from my car quad lock I won't need to worry about those, I guess if you have Bose then that's missing as RCA and remote wires run to the amp.

i have seen the cable that's missing, it has male phono plugs that must connect to the HU RCA to supply the audio then I just need to pin the rest and hopefully it's done. Will post back when I have it working.
 
The problem is the adapter will be quadlock to ISO and my HU doesn't conform to ISO :( so I would still need to custom wire parts. I will try and get the missing cable then hopefully I only need to custom wire a few cables. I can wire no problem but finding a description of the pin outs has been tricky. Getting there though, thanks for all your messages as they have helped me work out what's what :)
 
My quadlock that I have received is identical to the pins on my Audi quadlock except DSP EIN (no pin there) which is the remote wire for the bose amp so I will have to wire that one myself. Just adding info as I find it here so I can help others who run into the same issues in the future.
 
Ok new question, I need to add a pin to the quadlock as pictured in my original post, one of the spade type pins. What is the part for this? After about an hour of searching all I have found are these:
2-963725-1 - TE CONNECTIVITY / AMP - PIN, MQS, CONTACT / LOOSE PIECE | Farnell United Kingdom
965907-1 - TE CONNECTIVITY - CONTACT, SOCKET | Farnell United Kingdom

But they look like the pins for the blue/green sections as in the photos they are not spades. I can reuse one from the other side if I need to but would rather add a pin if I can find the part number.

Cheers
 
Finally think I have figured it out, I won't be able to test until the missing part of my ISO harness arrives but...:

0bgr.jpg


So Line RR, RL, FR, FL will connect to my headunits relevant RCA ouputs to provide the amp with an audio feed.

AUX-R, AUX-L will connect to my headunits AUX input so I can still use my headphone socket in my centre console as an input to the new headunit.

I assume both the Line and AUX earths will be wired to a common earth, if I have audio pops I may need to use an induction loop to fix this.

I have read the Bose pin can be left disconnected. If it is connected the Bose will use its own equaliser, if disconnected the headunit controls this. Am I right about this?

And no where can I find the definitive answer for the AU PL pin, is this the Bose AudioPilot pin? I assume this remains disconnected along with the Bose pin so I have total control of the equaliser?

I also need to add the DSP EIN pin to the ISO harness and this will connect to a remote wire to power on the Bose amp.

If anyone can correct me if I am wrong on this or confirm I am right I would appreciate it as it has been a big mess in my head, I am the sort of person who cannot rest until I have solved any problems that I encounter!
 
line outs and auxillary inputs will have a differant earth
purely to stop people connecting them up wrong and trying to feed an input into an output and blowing it up

for instance the headphone output in the car is not an input !!! do you mean 3.5mm auxillary input or an actual headphone output

as far as i know the bose pin is singular ...however it may indeed need a seperate pin to power up the amplifier itself
id suggest powering the headunit up and checking that particular connection to see if it outputs an earth or a 12 volt live
 
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Sorry, I meant the 3.5mm aux input, I tend to refer to that as a headphone socket so my clients know what I'm talking about!

From what I have read, the DSP EIN pin is the remote on for the Bose amp (perhaps non-Bose too) so I have connected that to the PANT wire and added the pin into the harness.

Oh and I had forgot, one last pin which has confused me, the headunit has a KEY1 wire for steering wheel controls (I am surprised there is only 1 wire for this...), where does this wire connect to on the Audi harness? AU PL is the only wire not officially accounted for.
 
i wouldnt reccomend connecting the remote wire for the bose amplifier to the power antennae output either

a remote output is fused at about 1 amp to stop the amplifier from feeding back when it fails the fuse blows
a power antennae output is fused about 15-20 amps this can do a lot of damage to an audio system in the time it takes for it to fail

id suggest powering up the stereo without anything connected then check the pins your not sure about with a multimeter to see what the outputs are doing
 
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Thanks for that, I was under the impression power antenna was another word for remote wire on this HU as there is no labelled remote wire. I will have to do some checking and see if I can find a remote wire elsewhere with my multimeter.
 
thatll be no then
was gonna suggest you drop it in and ill have a look , but its a bit far
 
Thanks for the offer :) I am hoping thatI can work around this and then type up a guide for those who can't afford an RNS-e or similarly priced unit and want to go for the cheaper chinese units made for the A3.

This is a clone of this device:
Zenec ZE-NC3131D Audi A3

But is missing some features.
 
Ok after a bit more reading up it appears there isn't a remote wire as canbus doesn't need remote so I can either:
  • Play around and try to find a switched 12v with a multimeter, but I will not know how it is fused
  • Run a remote wire to the fuse box
  • Insert an inline 1A fuse to the remote wire coming off the PANT, just need to check this is fed power when the radio is off and another source is in use
 
Mate, did you ever end up sorting this?
I’ve the same issue. Not having the brown orange connector. I’ve bought an aftermarket head unit and all the harness’ required. Plugged her in and no sound ...
What was your fix?