Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Unclip the hall sensor from below the turbine then
remove the connector from the hall sensor

Measurement:

Measure the resistance of each of the wires in the hall
sensor harness as stated in the table below.
Pin on connector X5Hall Sensor Connector
2 (White)White
3 (Green) Green
4 (Brown)Brown

Expect continuity / zero resistance on each of the wires.
Also visually inspect the harness for good general condition.