Set Appliance State:
Isolate Mains Power to appliance as per TOPs P4
Gain access to PCB (use insulation mat as required)
Disconnect connector X2 from the PCB
Gain access to PCB (use insulation mat as required)
Disconnect connector X2 from the PCB
Measurement:
Measure the resistance across Yellow wires on connector X2. The resistance should be approximately 120 Ohms.

Isolate as per TOPs P4
and refit as necessary