To save you reading it all....I cut n pasted it into one easy to follow guide....
Firstly make sure you've got the MP3 stereo (169 C1V2 MP3)
Then:
Buy one of these:
http://www.bluespot.co.uk/stock/auxin.asp
Then do this:
Removing the unit is simple - Either a cheap set of keys from Halfrauds, or a modded coathanger to depress the retaining pins on either side...A gentle pull, and out it comes...
You're left with a hole like this, in your dash...
Now this is where the problem becomes apparent - The multi coloured connector block occupies all available slots on the back of the head unit...So there's no place to plug the nice new lead in...
This might have been obvious to some, but as I'd never removed the stereo before, I wasn't sure if there would be a 'spare' port for the multichanger etc...There isn't...
Anyway, there's only one wire into the yellow block, but I'm not 100% sure what it's for, so just disconnecting it to insert my new lead wasn't an option...So I had no alternative other than to (carefully) butcher the new lead to free the wires...
This done, push them home into the relevant holes in the existing yellow connector (the three outermost ones on the left of the diagram marked AF L, AF R, and AF Earth)
THICK Black one is the EARTH and goes in the middle hole of the 3 holes
THIN Black & THIN Red are LEFT / RIGHT and go in top / bottom holes....
DON'T BUST THE METAL CLIPS!!!! THEY ARE FRAGILE!!!!
Now, I wanted to route the lead into my glovebox...Problem number two - There's no blanking plate to remove for the lead (thought there might have been one for fitting the official Fiat iPod lead). This would mean drilling a substantial hole for the lead...Around the area all the wiring for the passenger airbag is situated...
I've no desire to run the risk of setting it off in my face, or disabling it, so decided not to bother...Instead, I fed it down behind the head unit, and to the left...It comes out to the left of the centre console, and it's easy enough to tuck it behind, so that only what you need is visible around the cup holder area...
(Might revisit this later, but was in a rush, so no time right now...)
Leads all reconnected, head unit back into the slot, and it's good to go...iPod connects via the 3.5mm jack, and is distortion / hum free...Faaaaar better than any FM Transmitter I've owned...
(Instructions mainly from Fluoxetine with additional bits from erictheboy & me....
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