Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove the 3 wire connector from the fan assembly
Remove connector X2 from the PCB

Measurement:

Test 1:
Measure the resistance of the brown wire at the fan connector to pin 3 on connector X2.
Expect continuity / zero resistance.
Test 2:
Measure the resistance of the blue wire at the fan connector to pin 4 on connector X2.
Expect continuity / zero resistance.