Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect connector X6b from the PCB

Observation:

Measure the resistance between pin 6 (brown) and
pin 7 (blue) wires on X6b connector.
Resistance should be approximately 4.1kOhms.
Note:
If a white board is fitted connector is in same location but is called X6 instead of X6b.