Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Gain access to PCB (use Insulation Mat as required)
Ensure no demands
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Measure the voltage between the grey wire on CON6 to a suitable earth point.
With no demands mains voltage should be absent.