The fan body is earthed, including heatsink and back of the PCB, but it doesn't carry directly to a brush pair. Choke as I called it, is visible in the pinky-beige rubberised view of the control module (second photo).
Fan only has two speeds, it may be capable of more by design but that's how it is operated by this
PCM. Modes are: Off (cool weather, low load, no AC), Low (AC on, low to moderate engine load), High (all conditions exceeding these parameters or temp sensor failure). Module failure mode found by me is Low speed.
The engine only has one temp sensor; it informs the dash via the
PCM and CANBUS and also does duty for the
PCM itself.