zytec

I have a spare ECU, (taken from a 140 TDI 6 speed in a breakers), and would like to make it a useable spare so I can keep it in the car as a get me out of trouble unit.
Reading vag-com it appears you don't need a login for ECU swap.. (I don't have any logins... tried a few found searching the net but none work)

http://www.ross-tech.com/vag-com/cars/immobilizer2.html

However other information I've read talking about immo-2, (in relation to an A4, as I can't find anything related to my car specifically), below suggests a login is required:-

"This is Immo-2 where there is no difference between a new ECU and a used ECU because the ECU has no clue about SCKs.

With VAG-COM:

Select -> 17-Instruments -> Login.
Put in your 4 digit code with a leading 0 (01723)
Do It!
Hopefully, you won't get any error messages indicating the login didn't succeed. If you do, well your AD100 didn't read the PIN correctly.

Assuming the login "took", go to Adaptation. Leave channel at 00, click READ and click SAVE. Now back out of the cluster gracefully, then turn off the ignition for 15 seconds and turn it back on but don't start the car for a minute or so. At that point, you should be good to go.

-Uwe-"

Now mine I guess could be immo-1 if it makes much difference to the procedure?. I know It is a separate immobiliser unit under the rear seat so would be done in 25 rather than 17..

I'm really looking for confirmation from someone that's swapped out an ECU on one of these with another non new one.

According to Vag-Com A6 C4 after 95 has OBDII connector, however mine being a UK 1997 TDI, (and not a model supplied to the US market), could be why I've amusingly heard it referred to as a "Frankenstein car", and has the old 2x2 connector... does that mean it's not fully OBDII compliant?

Also the Haynes manual for my car, (which I know should be taken with a large bucket of salt), says, and I quote:-

"Always wait at least 30 seconds after switching off the ignition before disconnecting the ECU. When the wiring is disconnected, all the learned values are erased, however any contents of the fault memory are retained, After reconnecting the wiring, the basic settings must be reinstated by an Audi dealer using special equipment. Note that if the ECU is renewed, the identification of the new ECU must be transferred to the immobiliser control unity by an Audi dealer"

So to sum up, looks as if I can swap out the ECU and "tell" the, (separate), immobiliser to accept it with Vag-Com, (without requiring a login code????), but will I then be stuck with an ECU that has no settings and due to the fact I don't have a login, not be able to setup the basic settings?

I've done a fair bit of searching about to try to confirm this before posting here but there seems to be very little detailed specific info and I'd not want to do it until sure I'm not going to end up with either an unusable Car or ECU paperweights.

Sorry about the long winded explanation but had to get over the whole explaination.

some details....

Car is Uk spec 1997 A6 Avant (C4) 140 TDI (AEL)

I have a new Vag-Com Key USB with Vag-Com VAS-5051/2 adapter, Vag Com Version 512-4

ECU's are both the same 281 001 320/321 4A0 907 401 P

Theresias

Got a complete Auto-Scan handy? Is the immo module with address 25 reachable?

zytec

Thank you for the quick reply Theresias. I'm not at the location with the Vag-Com PC at the moment, but yes I've been in module 25 it's reachable, can't remember what's in it off the top of my head, however here's the detail from a printout the other day:-

Address 25: Immobilizer
Part No: 4A0 953 234 F
Component: Immo AUZ9Z0V2121233 D77
Coding: 00000
Shop #: WSC 00732

anything specific I need to check or look for?

Theresias

Ok, so always when the procedures say 17 (Instrument Cluster), use 25 (Immobilizer) instead.

zytec

No but I'm not an idiot either, spent 11 years as a mechanic in motorsport, but admit I'm new to Vag-Com, and trying to learn...

My original post was long and detailed for a reason, from this link;-

http://www.ross-tech.com/vag-com/cars/immobilizer2.html

"Note: For cars with a separate Immobilizer (Includes 2000+ EuroVan, Cabrio, and many older non-US models), use [25 Immobilizer] instead of [17 - Instruments]. The rest of the procedure is the same."

That and the fact I've swapped out instruments many times before on this car, (pre vag-com), and I know it has a separate immobiliser unit under the rear seat, leads me to the conclusion I need to use 25 immobiliser on my car.

I could just go ahead and do it on that info, but as highlighted it seems incomplete, and other info conflicts with it, as said I'd rather not end up with ECU paperweights and or a dead car...<ul><li><a href="http://www.ross-tech.com/vag-com/cars/immobilizer2.html">http://www.ross-tech.com/vag-com/cars/immobilizer2.html</a</li></ul>

Theresias

Looks like I'm missing your point, WHAT is incomplete or in conflict?

zytec

The info on Vag-Com's site suggests you can swap ECU using the info in the link shown in my original &amp; previous reply..

There is no mention of login, or requiring a login code... no problem except -Uwe- (see the detail in my original post), mentions login code when swapping ECU on Immo 2 versions... all be it not my car).

Like I said I'm not certain mine has immo 2 could be immo 1 as it has 2x2 connector.

On top of that my manual, (Haynes is similar to Bentley I think), bleats on about loosing "learned values" and "basic settings" needing to be input when ECU has been disconnected... see original post for more detail.

The basics of what I want to know are, can I swap my current ECU with the second-hand one taken from another car, (same model, same ECU), code it to my car so that it works, but all without requiring a login code, (which I cannot seem to source even from Audi). in other words make the spare ECU a usable spare that in future can just be swapped over if the need ever arises..

Sorry if I'm not explaining myself very well....

Theresias

...so I set them up for you in the new Wiki, based on the VW IMMO-I instructions. In your case you should have IMMO-1, but the Audi instructions are w/o login for ECU swapping.<ul><li><a href="http://wiki.ross-tech.com/index.php/Immobilizer_I_ECU_Swapping">http://wiki.ross-tech.com/index.php/Immobilizer_I_ECU_Swapping</a</li></ul>

zytec

Ok thanks, any idea what the Haynes manual is on about then or should I just ignore it namely the below which is specifically about the TDI according to the book, or at least it's in the TDI section..

"When the wiring is disconnected, all the learned values are erased, however any contents of the fault memory are retained, After reconnecting the wiring, the basic settings must be reinstated by an Audi dealer using special equipment."

Uwe@Ross-Tech.com

immobilizers in the clutsers. On those, it's necessary to do a login to the immo (in the cluster) before you can match the ECU to the immo in Adaptation Channel 00.

I don't think this applies to your car.

-Uwe-