Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect connector X4 from the PCB

Measurement:

Inspect the condition of the harness between the APS and the PCB.
Check for continuity (zero resistance) between the ends of the two wires running from the PCB to the APS.
Notes:
1. Remember if a white PCB is
fitted X4 is in a different position.
2. Colour of wires may differ
but pins will be in same location.