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The Engine Control Module (ECM), which determines the required fan speed, controls the level of clutch engagement. The ECM determines
engagement based on the coolant, charge air, ambient and transmission oil temperatures and the A/C pressure.
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An earlier post you did state the AC Tech said the pressure started a bit high,then the fan cut in,which is exactly what one of your graphs shows.
That should ring alarm bells.
yes thats what i was showing with the graphs, and he just thought the thermofan wasnt working and started looking for one, but couldnt find it, then we heard what sounded like a thermo fan start and run, and the pressure dropped to normal, later i realised its just the viscous engaging or not rather than a thermo fan.