MS-CAN inaccessible on Mondeo Mk3 TDCi (ELS27, or vLinker FS USB w/OBD-extension)
Posted: Mon Feb 17, 2025 1:58 am
I mentioned it in the vLinker FS USB post, but here again with more details:
the problem started with ELS27 which experienced trouble accessing modules on the MS-CAN bus in my car.
Specifically: SRM, EATC, ACM:

Later on, my ELS27 experienced a major failure - the FFC between the OBD connector and the PCB cracked and, obviously, any communication immediately ceased.
Now, when I got the vLinker FS USB interface, I immediately tested it to see if I could reliably communicate with all the modules in the car (as I had been able to before the failure). That worked OK, mostly. However, to have better access to the OBD interface (vLinker, ELS27, or whatever) I also got a relatively short piece of OBD extension:
It has 1:1 pins, but strangely the MS-CAN modules cannot be accessed if vLinker FS USB is not plugged directly into the car's OBD connector.
This is the situation in the log (two attempts are shown in it):

Sure, the initial green status comes from the loaded profile, so all modules stored previously are listed again. However, they do not respond when DTC read operations are attempted on FORScan initialization. Why does it behave like that?
the problem started with ELS27 which experienced trouble accessing modules on the MS-CAN bus in my car.
Specifically: SRM, EATC, ACM:
Later on, my ELS27 experienced a major failure - the FFC between the OBD connector and the PCB cracked and, obviously, any communication immediately ceased.
Now, when I got the vLinker FS USB interface, I immediately tested it to see if I could reliably communicate with all the modules in the car (as I had been able to before the failure). That worked OK, mostly. However, to have better access to the OBD interface (vLinker, ELS27, or whatever) I also got a relatively short piece of OBD extension:
It has 1:1 pins, but strangely the MS-CAN modules cannot be accessed if vLinker FS USB is not plugged directly into the car's OBD connector.
This is the situation in the log (two attempts are shown in it):
Sure, the initial green status comes from the loaded profile, so all modules stored previously are listed again. However, they do not respond when DTC read operations are attempted on FORScan initialization. Why does it behave like that?
