Aftermarket Pioneer HU radio issues - Fakra or ISO?

Ash187

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Hi guys,

OK so one of the first things i changed when i got the A3 was the sound system as i was used to bluetooth handsfree and iPod connections on previous cars and i hated the tape deck and 6cd changer it came with (symphony)... so i looked into it and didnt really like what Audi had to offer (inc the RNS-E) and decided to go down the Aftermarket route.

In the end i picked up a Pioneer P4200DVD unit with iPod video cable and bluetooth kit. at the time of the install i used a fakra to iso cable adapter which has never worked (this was a year and half ago) but i always use the iPod so i wasn't really bothered.
it looks like this:
Autoleads PC5-136 - Audi A3, A4 Amplified Fakra Aerial Adaptor ISO

recently i have developed a bug to iron out all the silly niggly issues in my car and this radio is one of them.

Now I have done some research and tried to look into fixing this issue i have but its one of the biggest things on this car that i can barely understand! the car has both an ISO and Fakra connector on the back of the old Symphony unit but why is there not an adapter that uses both the ISO and Fakra and then converts it to ISO again? I have found a twin fakra to ISO but not what i am looking for???

i found this old post which leads me to believe that i need a different adapter to the one that i have:
http://www.audi-sport.net/vb/a4-a4-...ndow-radio-amplifier-booster-help-needed.html

it suggests that i now need this adapter: CT27AA05 Aerial/Antenna VAG Active ISO Adaptor - Instal | eBay

just wanted some clarification on this as i dont want to go spending more money on wires that wont make a difference to the setup i currently have!

Also the blue wire on these adapters are meant to go onto a radio amp but i dont have one of those wires on the back of the HU so which cable do i connect that onto? the yellow, red or blue with white (one used to power up amps for subs)

also forgot to mention that my car does have Bose and that is working perfectly fine. (if that makes any difference)

thanks in advance guys.
 
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If you haven't connected the flying lead then that is why it won't work as this provides the 12v feed to switch on the aerial amplifier. This needs to connect to the aerial amp feed or amp remote on on the HU.
 
i have tried to connect that flying lead onto the blue/white cable behind the HU but that didnt seem to make any difference to the radio reception. thats why i am now thinking that i need the other adapter instead.
 
Thanks Andy, Just for my own understanding is there a specific reason as to why its better? i really want to understand what the damned fakra connection is. i like listening to Choice FM which is a London based radio station (also online) and sometimes they can have dodgy reception in certain areas which is why i would want to take advantage of both connections available in the car.