Technical Airbag Module CAN wires identification.

[CaliMac]

One evening started car up and dash randomly popped up with all the Airbag lights, flashing mileage and fuel cut off unavailable. When plugged into multiecu I had several errors in instrument panel/body control module/engine ECU. I could not access the continental airbag module at all using multiecu. See pictures of errors attached. I am trying to identify whether it is an issue with the CAN wiring, the airbag module, or the BCM.

I have verified I have 60ohms on the CAN system at the OBD port and my CAN H/L voltages and continuity from OBD port to pins on BCM connector. However I am struggling to identify the CAN wires/pins for the airbag module at the connectors. I have verified good power and grounds to the airbag module but nothing on either of the 2 airbag module connectors has continuity with the CAN pins at OBD/BCM and I am getting no CAN voltages present at either of the airbag module connectors. Which would make me think it’s BCM/Wiring related issue rather than the airbag module itself. I don’t fancy taking the dash out to physically follow the loom lol. Anyone advise pin layout for the airbag module connectors or where the CAN wires are fed from?

 

[GrandePunto PL]

No 2012 diagrams available for free. We have only eLearn for Grande. But most things should be similar to Evo/2012.
Start here (AirBag): https://4cardata.info/elearn/199/2/199000000/199000000/199000000/199002892
CAN structure for the car is here (but low res only): https://4cardata.info/elearn/199/2/199000000/199000000/199000003/199002596
OK, here (high res pictures, pin numbers): https://4cardata.info/elearn/199/2/199000000/199000000/199000000/199001200

If you are into diagnostics, you must have an oscilloscope, cheap toy one will do (then you can upgrade in the future, buy a real one).
CAN H and L signals are like mirror image (this example is an OBD2 port, pins 6 and 14).

 

[CaliMac]

No 2012 diagrams available for free. We have only eLearn for Grande. But most things should be similar to Evo/2012.
Start here (AirBag): https://4cardata.info/elearn/199/2/199000000/199000000/199000000/199002892
CAN structure for the car is here (but low res only): https://4cardata.info/elearn/199/2/199000000/199000000/199000003/199002596
OK, here (high res pictures, pin numbers): https://4cardata.info/elearn/199/2/199000000/199000000/199000000/199001200

If you are into diagnostics, you must have an oscilloscope, cheap toy one will do (then you can upgrade in the future, buy a real one).
CAN H and L signals are like mirror image (this example is an OBD2 port, pins 6 and 14).
View attachment 487230

Ahh perfect, Thank you very much. That is very helpful