Audi A4 B5 ASR/EDS Retrofit: Installation Guide

Okay, I've decided to retrofit these features on my A4. As far as I can tell, no one has tried this before, or at least not finished it.

Before I even start, I'm interested in finding out if there's an alternative ABS valve block and/or pump available for vehicles with ASR/EDS. If there is, I'll wait until my next brake fluid change. ^^

For the EDS (Electronic Differential Lock), the brake hydraulic system must be able to independently increase the brake pressure to the driven wheel. Does the 8D2 have an electronic brake assist system? If so, it should be capable of achieving this.

From an electronics perspective, it should theoretically only involve the control unit, some cables, and the ASR switch in the center console. Additionally, I need the ABS/ASR/EDS control unit coding from an A4 8D2, as I can't find anything specific. Or is there no coding required, and the functions depend solely on the control unit itself?

My questions, summarized again:

Is the ABS valve block the same for vehicles without ASR/EDS and for vehicles with ASR/EDS, or are they different? AKTE should be able to provide information on this.

Is a different coding required in another control unit (e.g., engine, ABS, ...)?

3. For the ASR (Anti-Slip Regulation) system to function correctly, the ABS/ASR/EDS control unit needs a fast data connection to the engine control unit (ECU) in order to implement the power-limiting commands. Does anyone happen to know how this data bus is connected on the engine control unit (ECU) (wiring diagrams)?

4. Does the 8D2 have an electronic brake assist system? If so, are there different versions depending on whether it has ASR/EDS or not?

I will also go to the today, ask them a few questions, and try to get a copy of the relevant wiring diagrams. They already think I'm crazy anyway. ^^

Okay, please don't start a discussion about the purpose of this upgrade. I've already read the other thread in the forum on that topic. Unfortunately, things didn't go well there.

If this renovation turns out to be too complicated, at least the issue has been clarified.

So, I went to the doctor yesterday and got some information.

"So far, the ABS module and the control unit for ABS/ASR/EDS need to be replaced (part numbers ABS 4A0 614 111 H or ABS/ASR/EDS control unit 4D0 907 379 N)."

The HBZ and BKV values are the same for vehicles without EDS/ASR.

In addition, work needs to be done on the wiring harness to create the necessary connections. I should probably receive the corresponding wiring diagrams this afternoon.


The biggest problem right now is getting the parts. The new price is around 2,500 euros, not including small parts. On platforms like Eb** and similar sites, you can only find the engine control unit (ECU) for the B4 model, and the largest control unit is for ABS+EDS.

I would appreciate it if I could get some feedback here. I'm especially looking for information on places where I could find the parts I need, such as scrapyards. There aren't many scrapyards near me (postcode 92533), and the ones that exist have very few or no Audi vehicles.

Hi,

I haven't written anything yet because I don't have any further experience with your specific modification. However, I can help you with the scrap dealer: http://www.kiesow.de/ is, to my knowledge, one of the largest scrap dealers in Germany. They might have something suitable for you.

If you find nothing about Kiesow, the following links might be helpful, although I only have partial knowledge of them.
http://www.autoverwerter.de/
[url]www.recline.de [/url]
www.autoteilemarkt.com/
www.autoteilemarkt24.de/

Searching Google for "Autoverwerter" might help you.

Good luck with the renovation.
Guste.

Thank you for the links.

I found nothing on Google. Also, searching by the part number didn't yield any results.

bastion wrote:

I found nothing on Google.

Also, searching for the part number yielded no results. }
No, you won't find them that easily. But there are other car recyclers. However, you won't get anywhere with them without calling, emailing, or faxing. They never list all the parts they have on the internet. That would be hundreds of parts per car that they scrap, and probably only 10% of those would be sold.

I wasn't just looking for the part number. Terms like "ABS module" and "control unit" didn't yield any results either. I did find some, but they were either without the EDS (Electronic Data Sheet) or modules from previous models.

I've now submitted a request for each link, let's see what comes back.

Not much came back, just a STG (Selective Torque Generator), and nothing else.

"I now have the wiring diagrams for the system. The wiring is simpler than I thought. There are only cables running to the EDS switching valves in the hydraulic unit and two cables to the instrument cluster: one for the speed signal and the other to the combination processor. The rest is mostly already routed by the ABS system."

Hello Bastion,

I'm not entirely familiar with the older ASR/EDS systems, but are you sure that a retrofit is possible?

EDS: I will investigate this further. The function is implemented in the ABS control unit, but it requires additional valves. These valves are needed to regulate the intake volume of the "active pressure build-up" system. "Active pressure build-up" means pressure generation without driver input. These valves are also used in the ESP (Electronic Stability Program) system.

ASR: Does your motor controller actually support the ASR interface? In the ASR system, the ASR typically requests torque reductions and increases from the ABS control unit, usually via the CAN bus, in order to regulate the desired wheel slip.
This message is also "monitored" to check if the connection or the other system component is present. Since you didn't have ASR, your motor system component probably won't support this function.

Best regards, and good luck anyway.


heating fossil.

heizfoss wrote:

Hello Bastion, EDS: [...] These valves also require ESP systems. ASR: [...] Does your MotorSG system actually support the ASR interface? The ASR system requires the MotorSG to reduce and then increase motor torque in order to regulate the desired amount of slip. [...] Since you don't have ASR, your MotorSG probably won't support that function.

EDS: Yes, that would require additional valves. However, according to the wiring diagrams, these valves are already integrated into the ABS/EDS unit. Otherwise, no additional valves were visible.

ASR: Yes, usually. However, only the gasoline engines have a connection to the engine control unit (ECU). With the TDI, I only found several connections to the instrument cluster (IC), including a combination processor and a speed signal. Apparently, the ASR system calibrates itself using the ABS signals and the engine speed. There might be a connection between the IC and the ECU, but I still need to check that. Supporting ASR in the ECU should not be a problem. It will be easy to code. From a production standpoint, it would be illogical to have different ECUs for engines with and without ASR. It's more economical to simply enable or disable the ASR function through coding.

However, I've put the project on hold for now, as the necessary parts are almost impossible to find. Not many A4 models were built with ARS/EDS, and the ones that were are still being driven.

Hello fellow enthusiasts,

I'd like to revive this thread, as I'm also considering the same idea (retrofitting the electronic differential lock).
With my '1-wheel drive' system, I can barely make it up my driveway, which has a 12% incline, even in snow.

After carefully studying the wiring diagrams, I've concluded that, in my vehicle, only the hydroblock (with the STG integrated) needs to be replaced.
You need to run a wire (pin 10 on the ABS/EDS control unit to T10b/9) to the connector block located on the A-pillar.
The workload would therefore be manageable...

Now, to the question:
The hydroblock with ABS and EDS has the part number 8E0 614 111 Q in the old parts catalog. You can find very little information about it in the relevant sources (except for a few completely dirty parts without covers for the open brake line connections...).
1.) What are the alternative part numbers (indicated by 'P' or 'AD' at the end)?
2.) Is there anything special to consider during installation (e.g., the pump may run dry if the plugs are not installed)?
3.) Does anyone happen to have a suitable part lying around?

Best regards, Kassen.

http://www.bildelsbasen.se/?index=default&link=item&post_id=20419267

You can buy from them, they've always been great! Although 300.00€ is a lot of wood.