Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove connector CN3 from the PCB
Remove the connector from the diverter valve

Measurement:

Measure the resistance between each of the pins on CN3
and the diverter valve connector as listed below:
Connector CN3Diverter valve Connector
Pin 1 (Black) Pin 1 (Black)
Pin 2 (Brown) Pin 3 (Brown)
Pin 3 (Blue)Pin 2 (Blue)

Expect continuity on each test.
Also inspect the condition of the harness, visually checking
for any damaged insulation.