ABS vs. EDS vs. ASR: What's the Difference?

I found a suitable control unit for my project. The part number is 4D0 907 379 M. I was told that it was later replaced by a control unit with the ending "N".

Therefore, my question is: Can I use this control unit, or will I encounter problems with it, or could it even cause damage to the vehicle?

The control unit has ABS with EDS and ASR. If you want to install the ASR, it is possible. You can also leave the ASR disconnected, which should also work, but then there will be an error message. The ASR should run via CAN. If you have a suitable engine control unit, you can connect the two wires, and it should work.

This is for an Audi A4 from the year 1996. It doesn't have a CAN bus system.

Then it's better to rely on a control unit with ABS/EDS. So, without ASR and ESP, etc.

ESP would likely be unique in an 8D2.

I also plan to install the ASR (Automatic Speed Recognition) system. How does the wiring work for that, and what about the engine control unit (ECU) coding?

You need an engine control unit that is designed for ASR (Anti-Slip Regulation). It should also include a CAN bus interface. Additionally, you'll need an ABS module and a corresponding control unit specifically intended for this purpose. Then, connect the Can-High and Can-Low lines from the engine control unit to the ABS module, and it should work.



For ESP (Electronic Stability Program), much more is required; the conversion process is more complex and therefore also more expensive. }

Um, I think we're talking past each other a little bit.

My A4, manufactured in 1996, was available with ASR (Anti-Slip Regulation) as a special equipment option, so I won't need a CAN bus system (which wasn't even introduced in the A4 until mid-1999) to retrofit ASR. Also, my question hasn't been answered.


What is the difference between the ABS/EDS/ASR control units with the suffixes "N" and "M"? Both support EDS and ASR.

Um, I think we're talking past each other a little bit.

My A4, manufactured in 1996, was available with ASR as a special equipment option; therefore, I won't need a CAN bus (which wasn't introduced in the A4 until mid-1999) to retrofit ASR. Also, my question hasn't been answered.

You don't have it built in from the factory; you need a CAN bus. Otherwise, I wouldn't know off the top of my head how you would get it to work. I only know about it through the CAN bus, although it might not be impossible for Audi to have a modified system installed there. I haven't delved into it that intensely yet.


What is the difference between the ABS/EDS/ASR control units with the ending letters 'N' and 'M'? Both support EDS and ASR.

If the control units were replaced with each other, the newer one certainly has different software, and possibly also different hardware. This is due to technical progress and bug fixes. It represents further development.

Please don't take this the wrong way, but what you're saying about CAN is complete nonsense when it comes to my vehicle.

I definitely don't need a CAN-bus for this, because it didn't exist in any Audi A4 models in 1996. There was also no modified version of the ASR system at that time. The ASR would have to be directly connected to the engine control unit (ECU) to transmit commands.

Please don't take this the wrong way, but what you're saying about CAN is complete nonsense regarding my vehicle. The ASR would need to be directly connected to the engine control unit (ECU) in order to transmit commands.

Okay. In the case of the Passat, which is a similar model, it's wired using two CAN lines (from the engine control unit to the ABS module) and that's how it works. The commands come from there and are executed. As far as I can remember, the A4 and Passat have a similar setup, which is why I thought of that.

I certainly don't need a CAN bus for this, as it didn't exist in any Audi A4 models in 1996. There was also no modified version of the ASR at that time.

How is it then structured and connected? I haven't delved into that so intensely before, which is what we can change now .

As far as I know, it works through a K-line connection or with a direct connection between the control units. I can't tell you much more because I'm just an amateur mechanic. ^^

As far as I understand, this is done via a K-line or with a direct connection between the control units.

This direct connection is the CAN line in the control unit. I should check the wiring diagram later; perhaps it will reveal how it's wired in the A4 .

But I think the others can help faster and better in that case.

Sure, I'd be very interested in seeing wiring diagrams between the ASR control unit and the engine control unit. ^^