Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
CH Demand
Main On/Off Control in the On position
Heating Control to Heating & Hot Water
CH Temperature Control to Maximum
Remove Yellow plug X12 from Motherboard and make safe
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

If a fault code is displayed press boiler 'Reset' button.
Remove Pump inspection cover.
Is Pump running?