Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove the connector from the fan
Remove the 3 pin connector from the PCB
Remove the 3 pin connector from the PCB
Observation:
Test 1:
Measure the resistance across the red and blue pins on the 3 way connector.
Expect open circuit / O.L.
Test 2:
Measure the resistance between the red wire of the 3 way connector and a suitable earth point.
Expect a resistance of 1 MOhm or greater.
(O.L is acceptable because this is greater than 1MOhm).
Are the resistances measured as expected?
Measure the resistance across the red and blue pins on the 3 way connector.
Expect open circuit / O.L.
Test 2:
Measure the resistance between the red wire of the 3 way connector and a suitable earth point.
Expect a resistance of 1 MOhm or greater.
(O.L is acceptable because this is greater than 1MOhm).
Are the resistances measured as expected?
Isolate as per TOPs P4
and refit as necessary