I am sending this schematic on the third page of the file you can see that the ECM controls fan and speed sensor ABS etc. I would still lean toward a bad connection at the ECM on the side of the block have you pulled this plug to check it?

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Although there are grounds that some of the items you are having problems with share it doesn't appear to be on the same lug only commonality is the chassis location frontclip, cab, bed etc.


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