Aftermarket head unit woes in my A4 B7

clockwork.satan

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Hey guys, I'm hoping someone can give me some help or even point me in the right direction as I'm just about tearing my hair out with this. My old Symphony II head unit went haywire a month ago so I looked into getting a replacement HU and found some nice looking aftermarket ones from Xtrons, so I managed to get one for a bit of a steal from Ebay and duly set about plumbing it into my B7 A4. It works absolutely fine and is actually pretty good, but I'm getting absolutely no sound at all from the rear speakers.

After a copious amount of time Googling things, I have figured out that this is a well-trodden subject but I just can't seem to find a straight answer. So far, I've figured out that my car is evidently not equipped with the Bose system, so I must have that amplifier for the rear speakers and the sub on the rear parcel shelf somewhere at the back. The only thing I can find from Xtrons is this page, which is not very helpful as I've never tinkered with a HU harness or OEM wiring looms before and fear that I'd mess things up.

I evidently don't have the blue 'amp-cont' wire (which I assume is found in Bose-equipped cars) and have read several different potential solutions to this issue, some requiring 'Hi-Lo converters' and stuff and others saying that I need an ignition feed and stuff.

Can anyone help?!
 
Well come to the after market head unit headache. There's been quite a few posts regarding this subject.

They do work on none bose systems as long as you be got the right connectors it should work. I faced same issue you can get lead from Halfords.

Where you based
Hey guys, I'm hoping someone can give me some help or even point me in the right direction as I'm just about tearing my hair out with this. My old Symphony II head unit went haywire a month ago so I looked into getting a replacement HU and found some nice looking aftermarket ones from Xtrons, so I managed to get one for a bit of a steal from Ebay and duly set about plumbing it into my B7 A4. It works absolutely fine and is actually pretty good, but I'm getting absolutely no sound at all from the rear speakers.

After a copious amount of time Googling things, I have figured out that this is a well-trodden subject but I just can't seem to find a straight answer. So far, I've figured out that my car is evidently not equipped with the Bose system, so I must have that amplifier for the rear speakers and the sub on the rear parcel shelf somewhere at the back. The only thing I can find from Xtrons is this page, which is not very helpful as I've never tinkered with a HU harness or OEM wiring looms before and fear that I'd mess things up.

I evidently don't have the blue 'amp-cont' wire (which I assume is found in Bose-equipped cars) and have read several different potential solutions to this issue, some requiring 'Hi-Lo converters' and stuff and others saying that I need an ignition feed and stuff.

Can anyone help?!

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Well come to the after market head unit headache. There's been quite a few posts regarding this subject.

They do work on none bose systems as long as you be got the right connectors it should work. I faced same issue you can get lead from Halfords.

Where you based

Sent from my SM-G935F using Tapatalk

Ta for the quick reply! I'm just outside Edinburgh.

I had a look in Halford's but couldn't figure out which connector I needed, and the staff were about as useful as a chocolate fireguard.
 
My unit works of the ignition I'm fine with that some don't and it kills the battery even if the unit shuts down. It doesn't turn off completely. Have you tried changing the Phono leads around. Even though they are labled for front right front left etc etc I got mines to work I have amplified sub in boot mines worked first time. I've even added a sub and it works great
Ta for the quick reply! I'm just outside Edinburgh.

I had a look in Halford's but couldn't figure out which connector I needed, and the staff were about as useful as a chocolate fireguard.

Sent from my SM-G935F using Tapatalk
 
My unit works of the ignition I'm fine with that some don't and it kills the battery even if the unit shuts down. It doesn't turn off completely. Have you tried changing the Phono leads around. Even though they are labled for front right front left etc etc I got mines to work I have amplified sub in boot mines worked first time. I've even added a sub and it works great

Sent from my SM-G935F using Tapatalk

I've not tried that, actually! I'll give that a go later and see if it has any effect. I did notice when I was connecting them that there was a 'pop' from the rear speakers so something was definitely happening.
 
Hey guys, I'm hoping someone can give me some help or even point me in the right direction as I'm just about tearing my hair out with this. My old Symphony II head unit went haywire a month ago so I looked into getting a replacement HU and found some nice looking aftermarket ones from Xtrons, so I managed to get one for a bit of a steal from Ebay and duly set about plumbing it into my B7 A4. It works absolutely fine and is actually pretty good, but I'm getting absolutely no sound at all from the rear speakers.

After a copious amount of time Googling things, I have figured out that this is a well-trodden subject but I just can't seem to find a straight answer. So far, I've figured out that my car is evidently not equipped with the Bose system, so I must have that amplifier for the rear speakers and the sub on the rear parcel shelf somewhere at the back. The only thing I can find from Xtrons is this page, which is not very helpful as I've never tinkered with a HU harness or OEM wiring looms before and fear that I'd mess things up.

I evidently don't have the blue 'amp-cont' wire (which I assume is found in Bose-equipped cars) and have read several different potential solutions to this issue, some requiring 'Hi-Lo converters' and stuff and others saying that I need an ignition feed and stuff.

Can anyone help?!

Do you know which version of xtrons you have bought? The older ones don’t have the blue amp cable but you still should be able to get it working without this.
Go into settings and set the fader more to the rear of the car and see if that helps. If not go to factory settings and the code to get in there is usually 126. Then go to voice, you will see some numbers that you can increase, try increasing these to the maximum which I think is 20 and then see if it’s made a difference. If not then I’d say it’s wired up wrong.
I once wrote a read about it for the a3’s with pictures and instructions but i can’t remember what I called it or anything
 
Do you know which version of xtrons you have bought? The older ones don’t have the blue amp cable but you still should be able to get it working without this.
Go into settings and set the fader more to the rear of the car and see if that helps. If not go to factory settings and the code to get in there is usually 126. Then go to voice, you will see some numbers that you can increase, try increasing these to the maximum which I think is 20 and then see if it’s made a difference. If not then I’d say it’s wired up wrong.
I once wrote a read about it for the a3’s with pictures and instructions but i can’t remember what I called it or anything

The model I've got is the PF71A4AS, which definitely doesn't have the blue 'AMP-CONT' cable I've seen on others. As far as I can tell, there's absolutely no sound coming from the rears as opposed to them just being quiet so I don't think the suggestion you've made will work - but I'll give it a go anyway! I've got a feeling that I need some sort of interconnect or something.

Useful to know the code, too - thanks!
 
Did you ever get this working?
I’ve got an A4 B7 non bose also.


I have the harness adapter from dynamic sounds but there’s no Amp remote output on my xtrons d719AS either.

I’ve tried connecting the harness remote output to “Ant power” and “ACC” both give an annoying buzz from the rear sub as soon as the key powers the circuit but no rear speaker sound.

Front speakers work fine.

Any suggestions to try like RCA ground loop isolators or something else.