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Retrofitting EOBD to a Golf 4 TDI?

 
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Blaumann
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Post17-11-2007, 20:12    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

Hello.

Is it technically possible to retrofit EOBD? I looked into the engine control unit (ECU). It should have the same pin configuration, but with different software. Also, the EPC (Engine Protection Control) light should illuminate on the dashboard when the ignition is turned on for diesel engines. What are the advantages and disadvantages of doing this? Normally, wouldn't it be enough to flash the non-EOBD ECU with EOBD software from a chip tuner? I also read a post today that for ARL engines manufactured from 6/03 onwards, a glow plug control unit that is diagnostic-capable was installed. Is it possible to retrofit this? It would be a huge advantage for me if the error log displayed a message when a spark plug is faulty. icon_biggrin.gif

Sure, here's the translation:

"MFG" is an abbreviation for "Mit freundlichen Grüßen," which translates to "Sincerely" or "Best regards" in English.
Audi SQ5 8R Cvub


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Post17-11-2007, 20:50    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

No, that is not possible.

General. Information: http://shop.dieselschrauber.de/obd-faq.php
Golf V GT Sport 1.4 TSI 125kW 11/07 - ... //images.spritmonitor.de/217524.png

Golf IV 1.9TDI 66kW 142Tkm 5/99 - 11/07


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pa-mm6
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Post17-11-2007, 22:10    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

Hello.

Okay, I'm not so sure about that. All the sensors and the CAN bus are available. I could imagine simply swapping the control unit and it should work then? Is there anyone here who has tried this before? The chip tuners should be able to simply copy the software for control units with identical hardware, and that should work too. What do chip tuners say about it?


Sure, here's the translation:

"MFg" translates to "Best regards" or "Sincerely" in English. It's a common abbreviation used in formal correspondence.
Audi SQ5 8R Cvub


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Jochen_145
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Post18-11-2007, 0:13    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

What do you hope to achieve with this?

You can directly read all the important information using VAG-Com.
The EOBD data is a standardized subset of the diagnostic data from the engine control unit.
Therefore, there is nothing in the EOBD that the MSG diagnostic system does not already offer itself.

The only difference is the MIL (Malfunction Indicator Lamp), which illuminates when exhaust-related errors occur persistently.
Furthermore, EOBD systems are generally much slower and less accurate than diagnostic systems, as manufacturers handle and disclose their 'internal' data differently.
At VAG, the general EOBD data is 'collected' by the gateway and made available.
Therefore, changing the MSG software alone will not achieve much.

Best regards, Jochen.


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Post18-11-2007, 21:59    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

Hi.

What do you mean by "collected from the gateway"? Are you referring to the CAN gateway? Is that the same for both 2002 and 2003?

Sure, here's the translation:

"MFG" is an abbreviation for "Mit freundlichen Grüßen," which translates to "Sincerely" or "Best regards" in English.
Audi SQ5 8R Cvub


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Jochen_145
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Post18-11-2007, 23:08    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

Hello,

Sorry, I don't know. At the latest with the introduction of the EURO4 standard, which was in 2004, the gateway will have to have this function.

The gateway collects the necessary measurement data from the CAN bus and prepares it in a format compliant with the OBD2 standard.

Best regards,


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pa-mm6
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Post19-11-2007, 10:50    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

Hello.

Okay, so the function is already available on my gateway. Since I have an 846 speedometer, which was installed from 2001 to 2005, there were no further changes made. I'm looking for someone who has a dataset from ARL with OBD information and can flash it onto my engine control unit.

Sure, here's the translation:

"MFG" is an abbreviation for "Mit freundlichen Grüßen," which translates to "Sincerely" or "Best regards" in English.
Audi SQ5 8R Cvub


Translated on 03-07-2026, 15:19.
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Jochen_145
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Post20-11-2007, 21:39    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

So, the function is already available on my gateway. Since I have an 846 speedometer, which were installed from 2001 to 2005.

Just plug in an OBD scanner and see what happens...

I'm now looking for someone who has a dataset from ARL with OBD information and can flash it onto my engine control unit.

Chip alla Chef
If that is the case, you know where to go icon_wink.gif.

Best regards,


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Post20-11-2007, 23:11    Subject: Retrofitting EOBD to a Golf 4 TDI? Quote

Hello,

You can always give it a try, but I don't quite understand the purpose or meaning behind it.
As mentioned in the title, OBD2 is only a subset of the standard diagnostic functions.

Best regards, Rainer.


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