Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Appliance drained and discharged
Remove the clip then prise out the internal bypass from right hand side hydraulic block
By-pass is located behind the diverter valve
Note.
The diverter stepper motor and valve body may need to be removed to gain better access

Observation:

Inspect the bypass valve for contamination and damage.
To confirm correct operation, ensure there is light spring tension.