Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect fan connector at fan

Measurement:

Test1:
Measure the resistance between the fan terminals as below:
Expected resistances as below.
TerminalsResistance in Mega Ohms
4 - 1Greater than 1 MOhms
4 - 2Greater than 1 MOhms
4 - 3Greater than 1 MOhms
4 - 5Greater than 1 MOhms

Test2:
Measure the resistance between each of the fan terminals and earth.
Expect open circuit for every test.