Re: Help please from people who have BOSE 147's
hello there, i drive a 156 gta with bose as standard and have just changed the rather rubbish standard fit blaupunkt head unit, this has the same fittings as in your photo, ie the main iso connector, plus the four wires which are grouped together in the green plug, these are the steering wheel controls, the only extra wire came from (i think from memory) the plug to the right of that in the photo which was a remote on (live) to the amp. the blue plug to the left was blank.the other aperture (oblong shaped) was also blank.
hope this helps.
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