Set Appliance State:
Mains Power Off
Mains Reset Switch OFF
Set Multimeter to AC Volts 
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Mains reset switch On.
Measure voltage across the red and white connections on connector marked H8 on the main PCB.
Mains voltage expected.
Measure voltage across the red and white connections on connector marked H8 on the main PCB.
Mains voltage expected.
Isolate as per TOPs P4
and refit as necessary