Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove connector X6A from the PCB
Remove the connector from the diverter valve motor

Measurement:

Measure the resistance of each of the wires in the diverter valve harness.
Pin 1 on X6A to pin 1 on the diverter connector.
Pin 2 on X6A to pin 3 on the diverter connector.
Pin 3 on X6A to pin 2 on the diverter connector.
Expect short circuit or zero resistance on each wire.
Also visually inspect the condition of the harness.
Are the resistances as expected and the harness in good condition?