My '18 started to shudder, no CEL, new plugs, new air filter, tranny fluid is good. CAN BUS codes show for TCM, PCM,DSC HU/MC, FWD CAMERA. they all interlink at J/C J-53, but I do not have a location even from the factory manual. Does anyone have the J/C locations?
I took it to a reliable mechanic and they got the issue down to canbus communication. I work with avionics canbus and going by the codes, the common tie point is the j/c c-53. No other modules outside that corner report in OBD. I’ll just have to split the harness by hand, in segments, and find the junction(s).
I believe afterwards but they’re OEM mazda. No codes pop for ignition. Supposedly they’re pre-gapped and no idea what the gap is for them. I seen a tb that states .030 or .033 but there’s nothing solid