Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect connector at top of pump

Measurement:

Check for continuity between the live wire of the pump harness to pin 4 (brown) of connector X2 and from the neutral wire of the pump harness to pin 5 (blue) of X6.
Also inspect the overall harness condition.