Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect connector marked X3 from PCB

Measurement:

Test 1:
Measure the resistance between the Brown (1) and Blue (2) wires at the disconnected connector.
Expect approximately 0.77 KOhms.
Test 2:
Measure the resistance between the Brown Wire (1) at the disconnected connector and Earth.
Expect resistance 1 MOhm or greater.
Test 3:
Measure the resistance between the Blue Wire (2) at the disconnected connector and Earth.
Expect resistance 1 MOhm or greater.