Set Appliance State:

Mains Power Off
Set Multimeter to AC Volts Set meter to measure AC Volts
NO demands
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure the AC voltage between the Live (Brown) and Neutral (Blue) wires at the fan AC connector (3 wire)
Expect mains voltage.