Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove the 2 red wires from the fan connector

Measurement:

Test 1:
Measure the resistance between the 2 exposed fan connector terminal.
Expect a resistance of between 40 and 95 Ohms.
Test 2:
Measure the resistance between one of the fan terminals and a suitable earth.
Expect a resistance of 1MOhm or greater.
(O.L is acceptable because this is greater than 1MOhm)
Are the resistances measured as expected?