Hello all,
Here to quickly put a few words together regards the recent evening works to this glorious A2. I must say coming from a generation 1 Chorus with only front speakers to now boasting a full suite of Audi A3 infotainment items along, aided with by the A5 FBMFSW with a complete Bose install is night and day from the first drive back in January. How it's coming along is just incredible whilst learning new skills to do all of my own work to keep the costs down. Another reason for the documenting of the following works is due to the amount of PMs I've received requesting assistance with replicating what's been completed so far. I thought it right to share my my own findings in public instead of behind separate PMs so the wider community can benefit from what I've been up to.
This post will be Bose focussed as it's fresh in my head and quite pertinent to the information request PMs recently received. This isn't a how-to; it loosely explains the way I conducted this particular retrofit to this specific vehicle. As a reminder, this A2 left the factory without rear speakers so the door side speaker looms had to also be added. Below is a picture of ear speaker looms along with the required (for this A2) earlier male/female speaker connectors:
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I found it easier to remove the door loom from the door so I could straighten the long rubber grommet to then push the speaker loom through. Quite a quick and easy task to remove the loom if you're familiar with removing the door cards and the aluminium cover, which has far too many T30 bolts in my opinion. This is the actual kit (
which is now no longer in a box which was set aside for a certain Dolphin Grey A2 but never quite made it into the vehicle) that is safely housed within the cabin, disregard the cut connectors as these were replaced for the full loom mentioned further down:
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First up for the Bose retrofit I highly recommend that you search for a full Bose kit where someone has removed the loom from the amplifier to up into the dashboard area, mainly not cutting the thick black sheathed cable containing the wires that go to the black 20 pin connector at the rear of the head unit, preferably ensure that the black 20 pin connector is still attached. If you're able to get your supplier to do this then you'll have pretty much all you need to conduct this retrofit yourself if you're of course confident at removing certain interior panels and seats, just as important is that you need to be well rehearsed at creating good solder joins for the minimal joins required should you get a full loom. Below shows a full (as full as required anyway) loom removed from the vehicle:
Full loom
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Loom at cut point high up in the dashboard where my hands could reach near the head unit aperture, only used the thick red wire (terminal 30) and 1x brown (terminal 31)(the second brown is the earthing for the shielded sheath which can be joined to the main earth out of the 2) and not forgetting the 4x speakers looms
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20 pin connector which provides amplifier on and the speaker signals from the head unit to the amplifier
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Here's the link that I used to build my knowledge a while ago ahead of taking this retrofit on:
Google Chrome should auto translate this link for you, you're mainly looking at the pinout explanation in the very first post
Hallo Ihr Lieben, Mütze hat mal wieder gebastelt: Ich habe einfach einen Boseverstärker an den vorhandenen originalen Lautsprechern angeschlossen. Dazu den vorhanden Kabelbaum vom Verstärker der hinteren Lautsprecher erweitert. Die Vorverstärkerleitung der vorderen Lautsprecher sowie Lautsprecher...
a2-freun.de
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In consultation with the above pinout information and being armed with an almost full loom that I removed myself (
which only took some 40 minutes from a breaker that had the seats removed and dashboard still in place) I quickly realised that the only joins to be made was the following:
Already in place for me
Pins 6,7,8,9,10 & 25 - are within the black sheathed cable so no requirement to join
Pins 14&15 were part of the full loom I removed
Required joins
Pin 11 - Terminal 31 Ground (I used the earthing point at the base of the A pillar)
Pin 13 - Terminal 30 Pre-ignition live (various places to take this feed from but best practice to take it to the fuse box as per factory and protect it with the specific rated fuse, do your research and refer to the electrical wiring diagrams)
Pins 16-23 for the speakers
If you already have rear speakers then you will less connections as you can use the same wires that you remove from the Blaupunt amplifier connector and push them into the Bose amplifier connector.
Yes for me, connection-wise the Bose retrofit was as simple as locating a suitable earth point and a suitable pre-ignition live feed followed by connecting the speakers up. Absolutely a DIY task if you're confident enough. There are of course other options available to you should you not be confident to do this kind of thing, this is just the way I done my own install last weekend, a very loud and satisfying outcome after settling for head unit powered front speakers only for some 9 months.
As for routing the loom I simply decided what was deemed as the easiest option by taking the earth to the base of an A pillar via the cross member, along the sill and bolted it down with a correct sized ring terminal compressed on. The pre-ignition live I took to the passengers footwell compartment with an inline fuse but will correct/move this to the fuse box in time so its exactly as per a factory solution, certainly totally safe the way it is right now though. The individual speaker looms were easy enough to route on the off-side of the vehicle as the amplifier is situated that side for you. I took the looms to follow an existing loom route along the cross member then up along the sills and loom taped them in place. The joins were made at the base of the respective pillar front (A) and rear (B) then into the door connectors themselves. The near-side was connected exactly the same but the routing had to cross the centre console area. With the front carpet removed you will see there are plenty of channels/openings available to reach the other side of the vehicle along the same cross member. The sheathed cable containing the wires to the black 20 pin connector were taken along the drivers side of the centre console area and up to the head unit aperture. Additionally on the black 20 pin connector I had to add the CAN wires, although this A2 left the factory without infotainment CAN I had already added them as part of the full DIS retrofit I conducted a few months ago with a later revision Q instrument cluster along with the later fuel sender in the fuel tank. The instrument cluster will be revised in time for the 3DColorMFD screen which I'm quite excited about. That's it, Bose fitted and fully tested this last week. Very very happy with the results of s few hours tinkering over 2 evenings.
As has been said on here many a time before me, although Bose doesn't produce competition-winning audio, it certainly is an improvement over the Blaupunkt setup and even more so if you've put up with head unit powered front speakers with no rear speakers for 9 months. I do admire the sound provided whilst comfortably sat in the recently acquired black alcantara heated sport seats, it really is a nice place to sit whilst out and about. Below is the main items housed in their new locations which is much better than in the garage safely stored in a box:
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Yes it's a bit dirty in there, I'll hoover it out at some point
I just read this post through and it started off with mentioning putting a few words together, think I have surpassed that now, apologies.
Kind regards,
Tom