ISO 9419 k line vw

So I have a 1994 golf that has k line but no obd2 functionality, using vcds and other iso 9419 reader software I can retrieve lots of data from the ECU.
Does anyone know If RealDash supports this protocol through OBD readers and if not has any used an Arduino library to interpret this data and then used the RealDash can protocol.

Many thanks

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Old K-Line is not directly supported by RealDash. We would very much like to add it as there are a lot of those cars around, but just have not found a proper documentation for the K-Line, or now VCDS for example communicates.

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I have done some research and found that my van uses old k-line (KW1281 protocol) and there seems to be a lot of documentation on this online.

Has anyone tackled this using an Arduino?

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Please view the attached link for the documentation regarding kw1281

There are many arduino sketches that make use of this protocol already in order to retrieve live data, my problem is how to transfer this data across to realdash

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Sorry for digging up this older thread, but this is something I’d like to know too! I have a '98 Passat and have been looking into k-line and kw1281 (sometimes called kwp1281), too bad that Volkswagen only published so little about it, even though it was standardized as SAE J2818 (that standard specification can be requested, for a fee, but is apparently quite useless).

I haven’t ‘observed’ myself that it’s actually kw1281 that’s used on my car, wouldn’t know how to (except for using VCDS, but I don’t have it). But all documentation I find online mentions that protocol for that model and year.

A few days ago I found this, however: kw1281test: A Free VDS-Pro / VagTacho Alternative | TDIClub Forums

Seems to be the most advanced reverse engineering effort, with quite some results. Something you can also do is extracting the skc (secure key code, needed when you want to ‘learn’ a new cluster, key, … to the ECU, so the ‘immobilizer’ doesn’t get activated) from the eeprom, not even VCDS/VagCom does that. He used the info on the link in the previous post for his development, but also other people’s reverse engineering efforts, and found out a lot himself by sniffing etc.

I’m tempted to try it, need to order a KKL cable though.

Maybe it’s useful… I wonder if somehow it can request ‘live’ data and pass it to Realdash, for example?
All these protocols, pin outs, … are quite confusing, also I’m definitely not a developer myself. So maybe it’s an unrealistic idea, still wanted to ‘pitch’ it though.

BTW, i don’t know if it’s relevant, but the OBD2 protocol works fine for that car, rpm, speed, … data are displayed nicely in Realdash. The shelll (monitor) reported protocol 3, iso9141-2 (5 baud init, 10.4 kbaud). If i’m not mistaken, the 5 baud init is specific to kw1281?. Screenshot in another topic : Beginner questions - #4 by berre

The fact that Arduino was mentioned, made me look online for projects. I found this one, which could be useful…?

The ‘kw1281test’ software is also open source btw, with a github, there’s documentation there too. The link is in that forum post but I’ll also drop it here, for convenience: GitHub - gmenounos/kw1281test: VW KW1281 Protocol Test Tool .

Thank you for linking this, I will take a look.

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I haven’t ordered a cable yet, I’m still looking into the different chips used etc. Not something I know an awful lot about but I’m learning :slight_smile: .
If useful, I can definitely provide you with test data, I’m not very eager to start writing to the eeprom using kw1281test (yet), but reading/dumping stuff is something I definitely want to do.

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I’ve been looking into it a bit more, one of the annoying things might be that ‘label files’ are going to be necessary, to understand what data is reported (the values only have numerical id’s).

After people started using Ross-Tech’s label files for their own software projects, they removed them from their web site.

However, I just installed vcds-lite and label files are included; searching through them with e.g. grep on linux should be enough, but I suppose every user will have to do that individually, based on the modules present in the car.
If support for k-line is added to Realdash (I hope it’s possible :smiling_face:), with or without an adapter with protocol logic, would one have to write a custom xml file based on the info in the label files?

Possible, yes. First version would just read some generic info like RPM etc, without possibility to customize with XML.

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do this and realdash will be even more famous and used by many, the vag kkl ch340 adapter can communicate with the k line however realdash does not have support for this adapter I ask you to carefully analyze my suggestion and add support for the k line