Disconnect the wire terminal from the "negative" terminal of the battery.
For clarity, some operations are shown with the instrument panel removed.
Pressing the latch..
... disconnect the block of the wiring harness from the block of the electric motor.
Disconnect the motor ventilation hose from the nozzle.
Using a Phillips screwdriver or a "7" head, unscrew the three screws that mount the fan.
We take out the electric motor with the impeller from the heater housing.
Install the heater fan in reverse order.