HELP !! no sound

cabby

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hi guys, i've tried several times to connect my multimedia headunit but i can't get any sound to come thru the speakers. i've connected the harness as descibe in some of the threads, orange wire to bose connection and all speaker connections look ok. blue flying wire grounded. still nothing.
can bus is in place on the harness.
have noticed next to the speaker conns to the audi conns a white con going to nothing on the aftermarket harness...looking on the diagram of the audi unit it as a symbol which looks like a
bridge thats open.
apart from trying to fit this unit myself, lol, what am i doing wrong?
the car is a full bose system
my mrs is sharpening the kitchen knife, think shes had enough of me.....help.
 
Which harness are you using?
What car is it?
The blue flying lead does not go to ground, it needs to be connected to the power antenna 12v (or "remote on" 12v). This is the 12v trigger that tells the Bose amp to switch on, so if you've grounded it then this is why you have no sound.
 
hello andy, a4 cabriolet 2.4 ...2002
the harness come with the unit,
ok, run that by me again, sounds like i need some more bits
where does this 12v antenna connection come from, there's just the aerial lead i unplug...
don't know much about what i'm doing.
i've got the new antenna adapter lead with it's blue wire connected to blue lead on the harness, still nothing.
 
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halfords want £45 for fitting and £46 for a harness they think i need, getting exspensive......
 
Don't let Halfords anywhere near it.
Post a pic of what you have at the moment, it's probably just one wire that needs correcting.
 
some p
DSC01873.jpg
ics
 
getting the hang of puttin photo's on posts, i'll soon be able to wipe my own nose..... well maybe.
 
Maybe select macro focus next time and give our eyes a break. Those are seriously out of focus, can't even see if that HU is aftermarket or not.
Need to see what is going on inside the block covered in foam
 
phone camera, crap, sorry....the 5 thin wires all close together are, 2 white at the top, black in the middle and 2 red under. a green to right of the cluster of 5 and then green/black.... bottom part, orange to bose, black and yellow feeds.
now seeing the limitations of my phone camera, must be time for an upgrade.
 
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We are only concerned with the top right of the connector in the last picture. These are the front & rear pre-outs to the Bose amp. There should be 5 pins, front right, front left, rear right, rear left and screen. Then there should be a 6th pin denoted by a switch on the diagram ontop of the HU. This is the 12v trigger that turns the Bose amp on/off with the HU. Without this the Bose amp remains off and you get silence. Can't see from the pic whether that plug is fully populated. There should be 2 top pins, 2 bottom and 2 in the middle. It is one of the middle pins that is the turn on for the amp. This should be feeding 12v to the amp when the HU is turned on.
 
the 6th pin denoted by a switch on the diagram on top of the HU, as no wire going to it from the new harness. the other middle pin as a slightly larger,black wire going to it from the new harness.
 
Yes that's the screen (earthed shield to protect the low level signal cables).
You need to take the power antenna feed or "remote on" from the new HU and splice it to the wire on the Audi harness going to the pin that goes nowhere (the switch). Use a piggyback connector if you don't want to cut the wire on the Audi harness.
 
well my boy, you are the man. (if that makes sense)
that was where i was going wrong with this, the blue flying wire needed that connection, as well as to the antenna.
i must say this, i now know how the bose set-up works. took awhile.
i wonder what leads Halfords would hav told me i needed!!! from the start i felt it was just a case of matching the right pins.
one more thing, the popping sound i have read about on many threads, is more like a bass bang. nearly jumped out of my skin. any thoughts on that one?

oh! i can't send you any ££££ but please name a charity and i WILL donate £20
regards John