Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove electrical connector from diverter valve (DV) actuator
Remove connector CN5 from the PCB

Measurement:

Measure the resistance of each of the wires in the diverter valve harness as follows:
Between pin 3 (blue) on CN5 and pin 2 on the diverter connector.
Between pin 4 (brown) on CN5 and pin 3 on the diverter connector.
Between pin 5 (black) on CN5 and pin 1 on the diverter connector.
Expect continuity / zero resistance on each wire in the harness.
Also visually inspect its condition.
Are the harness checks satisfactory?