Set Appliance State:

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

Measurement:

Test 1:
Measure the resistance between the 2 outer connections on the fan.
Expected resistance approx. 1 Ohm.
Please remember to take into account the
resistance of your probes when carrying out this test.
Test 2:
Measure the resistance between either of the outer
connections on the fan to a suitable earth point.
Expected resistance greater than 1M Ohm.