Information Difference 2001 TDi to 2002-04 TDi

Ricardo

A2OC Donor
I am looking to replace my written off A2 Sport TDi late 2002 with either a 2001 SE TDi or 2004 Sport 90PS TDi (known factors include mileage, price, options).

What I need advice from people in the know is what differences are there between 2001 and 2002 models?

Specifically I am looking to switch the interior from my 2002 to the 2001 (all of it) so is all the plastic compatible?

Will a Chorus head unit from '02 plug direct into an '01 - are there Canbus differences etc? Am I correct in assuming the secondary amp is a 2002 upgrade and so it and all speakers will need to be transfered to the '01 - will they work OK or again will the '01 electrics not support it. I have read about Canbus and early/late 2001 differences. If the 2001 car has a Chorus I then is it safe to assume the Canbus connection is of the older type hence Chorus II not plug'n'play?

Will the cruise from my 02 transfer easily?

Any advice to help my decision is appreciated.

I know the benefits of the 90PS but I also know it's got a dual mass flywheel and VV turbo which is more fragile/prone to carbon build up issues compared to the 75PS item and I can always chip the 75PS etc.

Many thanks in advance for input.
 
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Hi Ricardo,

You'll have no problem transferring the interior from one model year to another; all the interior plastics are the same irrespective of model year.

You will not easily be able to transfer the stereo head unit. As you correctly state, there will be wiring issues regarding the provision of CAN. Some members have got 'round this by fitting a CAN emulator. However, whilst I'm yet to give it a go, I'm fairly confident that I can upgrade 2001MY wiring to 2002-and-later wiring, thus allowing 2001MY cars to support Generation II head units as though they were fitted at the factory.

The secondary Blaupunkt amp is common as muck. Have you definitely established that the 2001MY car doesn't have rear speakers? The proportion of A2s that left the factory with only front speakers is quite small.
Should the 2001MY car not have rear speakers, they'll need to be retrofitted. Have a read of this thread: http://www.a2oc.net/forum/showthread.php?24257
You current car's door looms will be incompatible with those in a 2001MY car due to a change of connector type. These can be updated, though you'll need terminal extraction tools and general confidence working on car electrics. You'll also have to add wiring the the rear doors, the Blaupunkt amp, the fuse box and the back of the head unit. All things considered, adding rear speakers isn't much easier than retrofitting Bose.

The cruise control wiring is identical. If your written-off car had cruise retrofitted, that kit of parts will transfer with relative ease. If cruise was fitted at factory, you'll need a wiring loom, though the stalk can be reused. Engine management unit tinkering will definitely be required regardless.

If you don't mind me asking, where abouts are you in the UK?

Cheers,

Tom
 
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Nottingham/Leicester.

Many thanks for the reply, so the amp is for feeding rear speakers then? I didn't know that. The '01 car has rear electric windows which would be nice to keep.

Cruise was retrofitted by Sheffield Audi so wiring was added which can be moved so good again.

I would like to fit RNS-E in the future although I appreciate the single DIN issues - I am guessing it would be more sensible to go for a 2002+ replacement given the 2001 end date of the audio system. I assume 2002 onwards cars are similar as far as the data systems are concerned? So a 2004 car is more compatible with my 02.

I can cope with wiring but as ever time v benefit is an issue.

I need to test drive an SE too as I have only driven my Sport. That might make the decision for me.
 
Hi again,

That's correct - the little amp in the foot well is for driving the rear speakers only. The fronts are driven by the head unit itself. (This is all assuming you don't have Bose, though I suspect you'd have mentioned that if you did! :))

If the 2001MY car has rear electric windows, then you'd need to find some replacement door cards when doing the interior transfer. I'm guessing the motivation here is to keep the interior colour from your written-off car?

Retrofitting RNS-E to a 2001MY car is virtually impossible without embarking upon a major wiring restructuring exercise. I'm not aware of anyone who's done this. I doubt it'd be beyond me, but I guarantee there'd be a lot of head-scratching en route! :p
As you point out, you'd also need to do a dash replacement. That's not too big a challenge as long as you're familiar with the process, but getting hold of the replacement dash is tricky.

From 2002 onwards, all A2s share the same basic wiring. All the changes to connector types, wiring, CAN implementation and such happened between 2001MY and 2002MY. As such, getting a 2002MY or later A2 would make your mission easier.

Cheers,

Tom
 
Hmmm again many thanks.

Last question slightly off topic, but I appreciate that general consensus is to replace dash to convert single to dual DIN but why exactly. Is the aircon control panel not "cut down able" and if it is surely there just needs to be some sheet metal work internally to allow for mounting - the plastic itself looks the same or am I missing something?

Re: car - yes my interior is black, possibly replacement may be light grey. I guess the decision boils down to what I would like to retrofit later - if nothing then the 2001 is attractive as I get a set of SE wheels and rear electric windows too - already got x8 Sport wheels lol

Correct no Bose.
 
Double-DIN conversion is a little more complex than first meets the eye. Take a look at this photo: http://www.a2oc.net/forum/attachment.php?attachmentid=12095&d=1367366195
This is the double-DIN 'cage' that houses double-DIN audio/navigation gear. It's made of metal. You can modify a single-DIN dash to accommodate this cage. See http://www.a2oc.net/forum/showthread.php?22008
As you say, the single-DIN climate control panel can have its fascia reshaped to fit into the double-DIN cage.

A set of black door cards for rear electric windows can be found from time to time, so swapping your interior into the 2001MY car wouldn't be too big an issue. If you opt for the TDI90, which I'm guessing has manual winders in the back, then I'd be happy to do a rear electric window conversion for you if this is something you'd ideally like. We'd still need to find a set of suitable door cards for you, though.

As a note of interest, a 2001MY car with a grey interior will have the darker of the two greys (Swing) and a 2002-or-later car with a grey interior will have the lighter of the two greys (Platinum).

Cheers,

Tom
 
I would tackle the double din by removing plastic to physically get the units in. Then fabricate the necessary fixings to attach to out of some sheet stainless. But that's for another day...
 
Another option...

Given I have a 2002 donor car and plan on switching interior, dash, door cards everything. How silly would it be to also swap all ECUs and the loom?

I can even swap window motors (front) and door lock electrics if required. Or is the only real difference the audio Canbus issue and different connectors?

I've not worked on car electrics before but I have designed microprocessors...
 
How silly would it be to also swap all ECUs and the loom?

Um... fairly! This would be a massive undertaking. If you take the dashboard and the rest of the trim out, you'll see what I mean. The loom is an absolute beast, tightly integrated. Besides, it's simply not worth the effort. I'd sooner update connector types and add the necessary CAN wiring.

Cheers,

Tom
 
Many thanks Tom, so are the electrics the same apart from a switch in connector spec and the audio system being integrated into the Canbus ergo Canbus is the same?

If so, whilst the dash is out etc would it be possible to sort the wiring to configure the 2001 car to electrically match the '02 spec for future addition of RNS-E?
 
Yes, largely the electrics are the same.

A basic A2 has two CAN buses: drive CAN and convenience CAN.
A top spec' A2 will have four CAN buses: drive CAN, convenience CAN, infotainment CAN and navigation CAN.

In a 2002-or-later A2 with a Generation II head unit, the head unit sits on the convenience CAN unless the car has DIS, in which case the head unit sits on the infotainment CAN.

The instrument cluster acts as the 'hub' of the CAN buses, collecting data and passing it around as necessary. I'm not sure whether the 2001-and-earlier instrument clusters are internally more simplistic, thus restricting the amount of upgrading that can be done. Instrument cluster replacement would be an option, but getting your hands on a TDI cluster with DIS is tricky unless you're willing to buy a new one from the dealers.

I'm fairly confident that I could get Generation II head units to work in a 2001MY car by tying to the convenience CAN, but whether it's possible to get RNS-E working in a 2001MY car I simply couldn't say with any confidence without doing some more research and experimentation. RNS-E was never fitted to the A2 from factory, meaning there are no wiring diagrams showing this precise arrangement. Whilst I'm a great lover of spec', I have no desire to add RNS-E to my car, meaning I've never invested the time in fully understanding its integration into the rest of the A2's systems. Perhaps I ought to fill this hole in my knowledge. :)

Cheers,

Tom
 
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Where are you in the UK Tom?

So am I correct in the assumption that there is a single multi channel Canbus controller (each channel twisted pair?) and we can assume that the 02+ controller has more channels than 01.

So I need to transfer my 02 Canbus controller and connected wiring plus assume to have to change connectors where required and the Canbus controller (hub) is in the instrument cluster.
 
Where are you in the UK Tom?

I'm based in Lancaster, just off M6 Jct 33.

So am I correct in the assumption that there is a single multi channel Canbus controller (each channel twisted pair?)

CAN networks don't require a host, but nevertheless I know what you mean. Yes, all CAN channels are twisted pair and the instrument cluster resides on all channels.

...and we can assume that the 02+ controller has more channels than 01.

I've seen 01 vehicles with DIS and NAV, so I'd guess all four channels are available on earlier A2s. It may be that the only difference in wiring/electronics between 2001MY and 2002MY is the provision of CAN to the head unit. Audi changed from Generation I to Generation II head units at this time, so this was certainly one of the driving forces for the expansion of the CAN network. Although Audi seemed to make a big deal of it, the more I study the less significant the changes seem to be. With a bit of additional wiring, I suspect it's possible to do this upgrade, as long as there's no functional difference inside the cluster (such as the messages its able to send/receive). Whilst I can study the wiring diagrams, Audi don't provide any information about the specific changes within any ECUs from one revision to the next, so a cluster swap could be required. Without getting stuck in, I'm not sure how else to find out. However, as you've pointed out, you've already got a 2002MY TDI DIS cluster, so this could be used (with a bit of immobiliser/mileage tinkering).

Cheers,

Tom
 
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I think the summary of everything over the last few posts is that a 2001MY A2 could, with the parts available from your written-off TDI Sport, be adapted to suit you. It'd take some thought, but I reckon its doable! :)
 
Or I could just buy a cheapo A2 and re-shell mine :)) - but seriously your patience and thorough replies are much appreciated, it's been a real help, can't thank you enough.
 
Well the 2001 disappeared before I could get to it, so I went for the expensive option and have a shiny 2004 90PS Sport sitting on my drive. Funny how at a "genuine" 87000m it does not look in as good condition as my 200,000m car!

So I have managed to dodge the CAN BUS issues, but what I do need to do is:

1) Swap seats (easy)

2) Transfer my cruise control (probably OK)

3) Transfer my fog lights including headlight switch and surround (tricky?)

4) Swap steering wheels (easy - but weight a while after batteries disconnected etc)

5) Work our why the stereo in the 90 doesn't sound as nice as the one in my 75. Its lacking in mid range I think. 75 is Chorus II, 90 is Concert II. I am guessing its either the amp or rear speakers - or all 4 speakers. Any ideas on what the difference might be? I'll try swapping head units first then amps.

6) As I'm messing about with seats and wiring I might also see if my seats have heater elements, and if so have a go at a heated seat retro fit - any tips?

Also ... is there scope to move the battery from the boot to the drivers side underfloor cubby?
 
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