Another head unit post 2006 A3 8P

[craigy]

Hi people

I recently acquired an 2006 A3 TDI 8P its on a 56 plate if that makes any difference.

I want to swap the head unit to something with bluetooth or aux input as my fm transmitter sucks and i have virtually no radio signal for fm radio stations ( dead rear demister so likely related )

I found a head unit i like the look of and
Sony DSX A410BT
https://www.halfords.com/technology/car-audio/car-stereos/sony-dsx-a410bt-car-stereo-508694.html

im finding it hard to find the correct adapter, i have the concert headunit with the oem sub in the rear

halfords have 3 adapters listed but my googling has just made me more confused, from what i read

CT20VW02
CT20AU09
CT20AU10 - looks to have sub and rear speaker connections but unsure of the antenna

but i'm not convinced they would run the rear speakers and sub.

ideally i want a plug and play adapter i don't really want to mess about trying to run a wire for switched live from the fuse box if i can help it

any help is appreciated,

 

[J0N]

Halfrauds are actually pretty good these days but you need to call in and ask for their car audio expert. You need details of your new and old HU and any options you might have like BOSE or MFSW. They’ll ask you a series of questions from drop down boxes to eventually narrow it down to the harness you need.


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[NHN]

Is it a demister element issue or the modules, wiring feed affecting, also could be the rear radio coaxials, I would fix this 1st before swapping out the unit as if FM back it may change how you approach this change too.

 

[craigy]

Halfrauds are actually pretty good these days but you need to call in and ask for their car audio expert. You need details of your new and old HU and any options you might have like BOSE or MFSW. They’ll ask you a series of questions from drop down boxes to eventually narrow it down to the harness you need.


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I popped by today and ordered the headunit, facia plate and they are ordering in the harness fingers crossed the correct one, whilst there i picked up the keys to remove my oem unit

Is it a demister element issue or the modules, wiring feed affecting, also could be the rear radio coaxials, I would fix this 1st before swapping out the unit as if FM back it may change how you approach this change too.

no idea what it is, when i got the car a few months back the radio reception was bad, but it was only a few days ago i found the demister did not work since that's the first time i used it so i suspect something has gone that's affecting both, googling suggested the radio uses it as an antenna so likely a module had gone taking both with it.

i'm happy to replace the headunit as i would prefer bluetooth/aux and i can add in an aftermarket antenna if i decide to listen to fm although that is unlikely

 

[lleiro]

I installed the very same one last week. Quite happy with it. £65 off amazon + £20 for the fascia and adapter.

You will have to run and ignition wire from the fuse box and look carefully as you might have to swap red with yellow at the head unit. Also I had to fiddle with the blue wire firing up the rear amp but I made it work at the end but that depends on the harness that you get. Sounds great and does everything I need. Ask if you need more help

 

[lleiro]

Here is installed

 

[craigy]

Here is installed

looks brilliant,


i collected my stereo and returned the facia and harness today they ordered the wrong ones but now have hopefully ordered the correct ones for me to collect in a few days

halfords have now ordered these two, hopefully the correct facia if not i will have to order the three pack with for £30
CTHUP-AU01 harness
AudiA3 03-06 Fsc Kt

fingers crossed with this harness, it should be all plug and play no ignition wire or anything required just plug the amp into the head unit and the correct two RCA cables

the first ones they ordered were these two
CTHUE-AU1 harness
CT24AU07 faceplate

 

[lleiro]

Thanks. I don't think you can avoid having to run an ignition wire on your own because at least on my 8p there is none in there and the stereo needs one.

This video helped me immensely:


And the blue wire firing up the rear amp I had to figure out on my own following the schematics of the sony HU and the oem head unit.

Good luck!

 

[lleiro]

For what is worth I went with this kit

amazon.co.uk/gp/product/B074V84B78/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1

and while it was frustrating due to the lack of proper instructions I made it work.

 

[craigy]

Thanks. I don't think you can avoid having to run an ignition wire on your own because at least on my 8p there is none in there and the stereo needs one.

This video helped me immensely:


And the blue wire firing up the rear amp I had to figure out on my own following the schematics of the sony HU and the oem head unit.

Good luck!

installed the headunit today, halfords are still waiting for the faceplate,

my harness came with a canbus adapter so no ignition required just plug and play

i do have a weird issue my rear speakers/sub seem really quiet i have to set the fader to rear by 10 clicks on the dial

subs getting power but just quiet the rear seems quieter

 

[lleiro]

I got that same feeling with mine but I guess I did not spent enough time with The oem to tell them apart. I only needed 3 clicks to the rear to balance it out. Non-bose on my case

 

[craigy]

I got that same feeling with mine but I guess I did not spent enough time with The oem to tell them apart. I only needed 3 clicks to the rear to balance it out. Non-bose on my case

small update, fixed the low audio for the rear,

i bought an autoleads line output converter (PC1-601) from halfords after some googling of my issue , i have removed the RCA connections from the back of the head unit and used crimped on bullet connectors to attach the line output converter to the head units rear speaker wires and bingo rear audio back to the same levels as the front,

The RCA plugs for the rear now plug into the converter, two of the rca cables are redundant they don't connect to anything in my harness so when i'm next in there i will remove them from the block

All made easier as thankfully as the cthup-au01 harness has bullet connectors for everything going into the iso block so i can easily disconnect the rear speakers,

one annoyance the can box thing wont sync, flashes green then solid red no matter what i try but the live and switched live work as they should so no big deal,

strangely i did wake up to a dead battery and non functional 12v accessory socket this morning, im hoping its unrelated i got to check the fuse when its not raining and i have a feeling it could just be my battery having bad cell, watching the voltage on the head unit and it was dropping off fairly quickly,

im keeping the HU disconnected tonight to rule that out and fingers crossed it's not raining so i can check the fuse tomorrow

image of my harness below (CTHUP-AU01)

 

[lleiro]

Before getting the A3 I installed an OEM newer VW unit on my Touran and that was one of my biggest fears as they are countless reports of a flat battery related with CAN adaptations of head units. Fingers crossed is not your case

 

[lleiro]

small update, fixed the low audio for the rear,

i bought an autoleads line output converter (PC1-601) from halfords after some googling of my issue , i have removed the RCA connections from the back of the head unit and used crimped on bullet connectors to attach the line output converter to the head units rear speaker wires and bingo rear audio back to the same levels as the front,

The RCA plugs for the rear now plug into the converter, two of the rca cables are redundant they don't connect to anything in my harness so when i'm next in there i will remove them from the block

All made easier as thankfully as the cthup-au01 harness has bullet connectors for everything going into the iso block so i can easily disconnect the rear speakers,

one annoyance the can box thing wont sync, flashes green then solid red no matter what i try but the live and switched live work as they should so no big deal,

strangely i did wake up to a dead battery and non functional 12v accessory socket this morning, im hoping its unrelated i got to check the fuse when its not raining and i have a feeling it could just be my battery having bad cell, watching the voltage on the head unit and it was dropping off fairly quickly,

im keeping the HU disconnected tonight to rule that out and fingers crossed it's not raining so i can check the fuse tomorrow

image of my harness below (CTHUP-AU01)
View attachment 212265

Did you take any pics? I am pretty sure my rear speakers are shy so I'd have to take your route. All working good now?

 

[craigy]

Did you take any pics? I am pretty sure my rear speakers are shy so I'd have to take your route. All working good now?

so late to this reply, for some reason i did not get any notifications and forgot to check and it slipped my mind. everything works as expected, my battery issue was exactly that

I paid for a service the week prior to installing the radio and chose one where they should have also checked my battery and topped up fluid etc and advice if it needed replacing they did none of those things im even unsure they changed oil and filter but trusted them as it was a family members friends garage but never again. so when i did check the battery a few days later it was dry as a bone with both end cells ruptured,

I will put a link onto my desktop and tomorrow get pictures of how i installed the PC1-601
i also pruned off excess wiress from my harness adapter to make it look cleaner,

i will clarify from my previous post exactly how i did the PC1-601 wiring
plug the RCA cable from the harness adapter into the PC1-601
now as my harness used bullet connectors for everything the 4 speaker wires from the line level adapter as they had no ends i crimpt on the same size bullet connectors and connected those to the harness and i believe one was for power but i will check and update tomorrow as it was 2 years ago

i will edit this post and insert images

 

[craigy]

unfortunately i cannot edit the post, went out to the car to take pictures and well i forgot i wrapped the wires in harness tape so can't get any pics of whats going where, but the PC1-601 5th wire should go to ground, just check your wiring diagram for the head unit so you know what wires are for the rear speakers, and bear in mind this is for the half amplified system not the bose setup

white (+) left channel

white/black (-) left channel

grey (+) right channel

grey/black (-) right channel

black -- earth