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So ive had a stalled car for a while and diagnostics says its a module communication error. BCM and pcm dont communicate. Took some time to learn about can bus and oscilloscopes and finally took a peek and I was hoping the problem would be obvious but it doesnt seem to be erratic readings like what I saw while educating myself. Im at my wits end and if its just a module replacement id rather save myself the 500 dollars of labor a shop would charge. I checked the gm low speed lan and the readings look good. I unplugged modules on and off and readings didnt change. Checked all power and grounds and nothing seems off. Any ideas? Only three modules in the high speed bus. BCM, Steering, and pcm/ecm. Ive yet to check the grounds and 5 volt reference with the oscilloscope but multimeter showed them as fine. I think ill do that maybe the oscilloscope will show a fault there? Any suggestion from an experienced person would be much appreciated. I also replaced the steering module as I thought it would be the issue since it links the pcm and bcm but that did nothing.
P.s. Do those readings look fine? Im using a 1x probe. Since I have only videos and some posts from google to reference im basing myself off of that and well in those cases its obvious to see something is off but in my results they look fine? Yellow is high speed can + blue is -.