Transmit and Receive ID, ISOTP -8260?

[pavao_barisic]

Hi

I'm working on a project for my college that includes testing compatibility of vehicles with LabView 2011 and NI USB-8473s. 

I created some of my own .vi-s but later found out about ADCS examples and OBD car monitor demo. For my project I have to get DTCs from CAN bus, and there comes the problem.

My proffesors car is Citroen C-crosser which is fully compatible with examples (Get DTCs and OBD engine monitor). On the other hand there is Audi A4 (2006 model) which is compatible with OBD engine monitor.vi but not with Get DTCs.vi (ISOTP error-8260 appears). And there is Seat Ibiza (2010) that is throwing ISOTP -8260 error for this combination. I understand basics of CAN frames and messages but one thing is mistery to me. How does the other diagnostic equipment (for example this) knows which transmit and receive ID is CAN bus for all (supported) vehicles using?

A lot of you here says that it should be 7E0 and 7E8 which is true for C-crosser, not true for Ibiza and partialy true for Audi. Audi uses 7DF for transmit rather than 7E0.

I found in ISO 15765-4 a table which is  explaining what transmit and receive ID is using which ECU. So ECU#1 uses 7E0 and 7E8 but why is audi using 7DF and 7E8 and how to find out which is Ibiza using?

One more thing is strange to me... why does the audi give 8260 error if I try to run Get DTCs.vi from examples but runs normally with OBD engine monitor.vi?? Both of the .vi-s are using same open diag.vi.

While searching the forum I found people with examples that use transmit and receive IDs which are not in ISO 15765-4. Where did they found out about them?

Any info is very very appreciated.

[Daniel-H]

Pavao,

Unfortunately, these examples as well as the products are not designed to work with all makes and models of vehicles.  The cars you mentioned are all European made which makes me less confident in their ability to work with these prebuilt examples.

I also cannot speak to the functionality of other hardware. I assume there is some configuration done on the user's end.

Daniel Herrington

[JanosV]

Hello!

I am facing the same situation like yours in the past.

"While searching the forum I found people with examples that use transmit and receive IDs which are not in ISO 15765-4. Where did they found out about them?"

Could You found any information about this? I would be very very happy, if You could help me with some info.

Thanks in advance!

[Hooovahh]

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@JanosV wrote:

"While searching the forum I found people with examples that use transmit and receive IDs which are not in ISO 15765-4. Where did they found out about them?"

Could You found any information about this? I would be very very happy, if You could help me with some info.

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For me it was the 4th link in Google, but then again I maybe biased on the amount of times I visit it.

https://hooovahh.blogspot.com/2017/07/can-part-8-iso-15765-kwp2000-odb-and.html

The code posted there is kinda rough, but the logic behind the protocol should be good, just the individual implementations could be better.  I've since used a hardware abstraction layer with classes which cleans things up a bit.