Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove connector 100 from the PCB

Measurement:

Test 1.
Measure the resistance between the brown and blue wires on connector 100.
Test 2.
Measure the resistance between the blue and earth wires on connector 100.
Test 3.
Measure the resistance between brown and earth wires on connector 100.
Expect a resistance of greater than 1 MOhm for each test.
Note.
A reading of O.L is acceptable as this is greater than 1 MOhm.