Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
CH Demand
Selector Switch in CH CONTINUOUS position
Remove connector plug from X2 on PCB

Measurement:

Measure the resistance across connection 01 (White wire) and connection 02 (Black wire) on the disconnected plug.
Note: Measurement taken at disconnected plug not PCB.
Replace plug after test.