Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4

Observation:

Check preheat control knob is fitted correctly, the control knob should move between Off / On with a click when it fits into each position and it should not be possible to move the knob past either position.
Note:
If appliance does not have preheat (blank plug fitted instead of knob) then select "Appliance does not have preheat" below.