Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove connector J1 from the PCB

Measurement:

Test 1:
Measure the resistance between the pin for the brown and a suitable earth.
Expect a resistance of 1 MOhm or greater.
O.L is acceptable because this is greater than 1 MOhm)
Test 2:
Measure the resistance between the pin for the blue and a suitable earth.
Expect a resistance of 1 MOhm or greater.
O.L is acceptable because this is greater than 1 MOhm)
Are the resistances measured as expected?