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 X6 from the PCB

Measurement:

Measure the resistance between the red wires of X6, marked 9.1 and 9.2.
The resistance should conform approximately to the table below: