+- OrBit Forums (https://forums.spaycetech.com)
+-- Forum: General (https://forums.spaycetech.com/forumdisplay.php?fid=1)
+--- Forum: OrBit Q&A - Ask your questions here! (https://forums.spaycetech.com/forumdisplay.php?fid=24)
+--- Thread: Direct device diagnostics (/showthread.php?tid=208)
Direct device diagnostics - Wevie - 09-08-2023
Hi all,
After years of experience in mostly German vehicles I recently started working on recent Volvo and Polestar vehicles.
When I was working on specific vehicles in the past I was using a generic gateway from a donor vehicle, which allowed me to connect ECU's to (at the correct CAN Bus etc.) to do diagnostics on that ECU on my bench outside its host vehicle.
Would Orbit (and Volvo/Polestar) allow a similar setup? I.e. Can I use a donor VGM to connect to a different ECU like a IHU4?
Or is the pincode mechanism etc completely failing that way?
RE: Direct device diagnostics - Power6 - 09-11-2023
This is a pretty clever idea for sure. Of course there are many considerations, things that may or may not work, I think if you have experience with this, you are aware of the challenges with this, things like the ECU you are working on can't talk to the other ECUs, what problems does that cause for the ECU you are working on etc. There are so many possibilities we can't be exhaustive, those things will have to come out in practice. But again, I think you understand the unknowns that are associated with this.
I can tell you what I know. I think this can work, I forsee a few hurdles, in two ways, related to the architecture of the car ECUs running on the bench, and then how OrBit could work with this. I'll give you some points for these. Maybe you have some ideas, how to make this work, as I am interested in building this as well ;-)
For the "bench" ECU things to consider:
- The VGM gateway is secured by a diagnostic firewall. This is why the "VGM PIN" is needed for the Android based cars, to disable the firewall for advanced service functions and programming. The previous VCM gateway does not have a firewall. As long as you have the VGM PIN for your bench VGM you will be OK. To get the VGM PIN you are going to at least need to know the VIN of the car the VGM on your bench came from. Then you could use our "PIN Service" to get that PIN. Maybe using a VCM would work for all the ECUs you could work on to sidestep the VGM security.
- There is a FlexRay network in the car. Some ECUs will only respond to diagnostics on the FlexRay connection even though they have a CAN connection as well (the CEM is one of those) I am not sure what it takes to reproduce FlexRay network on the bench. It's not a CSMA network like CAN Bus, it is TDMA. Those are technical terms but it means in practice you can't just add and remove nodes like a CAN network, there are defined nodes with timing. I don't know much more, like whether a FlexRay network functions if you have "missing" nides, is there a master node that negotiates the nodes present on the network. That needs some reasearch and playing around to learn.
For OrBit connection:
- This one may not be so bad if you got a working bench ;-) Well I am the developer, so if we need to change something, then I can probably do what is needed to make it work.
- OrBit does expect a functioning car with all ECUs present. it also associates a car with a VIN, and that VIN, which comes from the CEM, has a "profile" of discovered ECUs and part number info, used for reference when performing functions.
- I don't see it being a problem to come up with a "bench mode" where OrBit can work without expecting all ECUs to be online, and I think we could have a way to work with the profile system when you have changing ECUs on a bench setup. I am willing to make that work if it's not a total nightmare ;-)
RE: Direct device diagnostics - gren - 10-18-2023
For the getting the VGM pin part - couldn't you just read the VIN on the VGM by reading the DID for VIN? Assuming you had a VGM with an unknown parent VIN, should still be easy to retrieve the VIN I think.
A bit curious on the VGM firewall - does it blacklist certain service identifiers from being relayed to the proper ECU without proper authentication? Since it seems to me you can at least read DIDs from all the ECUs without any issues and with no additional auth.