Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Gain access to PCB (use Insulation Mat as required)
Disconnect connector CN1 from the PCB

Measurement:

Measure the resistance across the blue wires on connector CN1.
Resistance should be open circuit.
Turn hot tap ON.
Again measure the resistance across the blue wires on connector CN1.
Resistance should now be short circuit.
Note: On some PCB's the connector will be labelled as CON3 not CN1 and its orientation will differ, however the test points and expected results remain the same.