VW OBD-II / CAN Bus interface questions

jasonsp6 · 09-19-2003, 10:41 AM

Hi, I have a 2002 GTI that I was going to use an OBD-II interface to log some data real time. I was wondering if OBD-II is the same pair of wires / same protocol as a CAN BUS, which is connected to various components in my vehical, including the OEM stereo. (That is how the factory stereo is currently turned on and off... and also can run for a period of time without the key in the ignition.).

Has anyone in this group played around with the CAN bus in an automobile... VW or Audi to be specific?

Any knowledge will be appreciated!

~Jason

jasonsp6 · 09-22-2003, 08:21 AM

Has anyone out there experimented with the CAN bus? Information regarding this seems to be very minimal across the internet.

TheSpatulaOfLuv · 10-13-2003, 03:37 PM

You may want to check out Rosstech - the folks that brought us the VAGCOM. They sell a software package that interfaces with VW ECUs to clear codes, etc. Perhaps taking their application and running it underneath a VB program that displays gagues. I'm curious to try the same thing in my bug, but I'm still acquiring parts for my project, and am in no way near this phase of the project. I've always thought it would be cool to have a fully custom gague panel for my car - I'd definately lock down a few trophies at the next car show for that one!

Once I get the rest of my hardware, I'll start playing with our club's VAGCOM software to see if there's a way to do this realtime.

jonee · 03-21-2004, 11:16 AM

I'm also trying to figure out how to interface the Can BUS in my VW Touareg.
I guess it has a lot more options than the OBD Interface.
OBD can easily be interfaced with using Ross Tech's VAG-COM but i've never seen a PC communicate with the CAN BUS.
If anyone out there did this already, please provide info.

none · 03-21-2004, 11:25 AM

You want VAG-COM, no other software comes close for our vehicles. Not sure about the CAN bus in particular, but anything that can be accessed on VAG cars can be done by VAG-COM. And yes it can be done in realtime, and it already has virtual gauges.

Check out the forums at Audiworld or VWVortex for more expertise on this subject.

jonee · 03-22-2004, 03:46 AM

Ok, can you tell me if it's possible to monitor the steering wheel and nav screen buttons?
And how do I write some text to the centre display (between speedo and rpm).
And where do I connect this cable to if I don't want it to be visible. The OBD plug is visible inside the car, I don't want to see any cables when a carpc is connected to it. Is there another location with an OBD plug?

none · 03-22-2004, 11:07 AM

Like I said, VWVortex or AudiWorld is the place for these questions. AudiWorld has a whole subforum dedicated to VAG-COM.

roverron · 03-23-2004, 08:23 AM

Quote: Originally Posted by jasonsp6

Hi, I have a 2002 GTI that I was going to use an OBD-II interface to log some data real time. I was wondering if OBD-II is the same pair of wires / same protocol as a CAN BUS, which is connected to various components in my vehical, including the OEM stereo. (That is how the factory stereo is currently turned on and off... and also can run for a period of time without the key in the ignition.).

Has anyone in this group played around with the CAN bus in an automobile... VW or Audi to be specific?

Any knowledge will be appreciated!

~Jason

The Can bus is completely separate from OBDII; its a bit like comparing a PC's network port to its serial port.
VAGCOM's OBDII software enables you to access most if not all of the CAN bus devices in your VW via the OBD connector & protocols.
So forget the Can bus just use VAGCOM. (from Ross-tech.com)

jonee · 03-24-2004, 01:05 AM

Fine, but I don't want a CarPC with a HEX USB cable running over the dashboard connected to the 'visible' OBD2 port.
Unless of course there's an invisible OBD port.