Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove connector X2A from the PCB

Measurement:

Test 1.
Measure for resistance across pins 2 (black) and 1 (blue) of connector X2A.
Resistance should be approximately 4.1kΩ.
Test 2.
Measure for resistance across pins 2 (black) and 4 (green/yellow) of connector X2A.
Expected resistance greater than 1MΩ (or O.L).
Note:
Wires may be multicoloured.