Just like almost all systems on that car! there are several computers involved in the operation of the engine cooling fan assembly.

Engine computer sends temp signal to the A/C control panel via the instrument cluster.
The instrument cluster also passes signal info from the A/C controller to the front SAM (signal activation module) via the EIS (electronic ignition switch). from there the front SAM sends a PWM signal to the fan control module.

Sorry if this doesn't help..BUT nothing is easy w/o computer to diagnosis.

Could be a programing issue with the A/C controller OR any other computer involved.

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