Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove connector X3 from the PCB
Measurement:
Test 1:
Measure the resistance between the blue and brown wires on connector X3.
Expect approximately 160 ohms or greater.
Test 2:
Measure the resistance between the brown wire on connector X3 to the earth at the incoming mains supply.
Expect a resistance greater than 1Mohm.
Are the resistances as expected?
Measure the resistance between the blue and brown wires on connector X3.
Expect approximately 160 ohms or greater.
Test 2:
Measure the resistance between the brown wire on connector X3 to the earth at the incoming mains supply.
Expect a resistance greater than 1Mohm.
Are the resistances as expected?
Isolate as per TOPs P4
and refit as necessary