Set Appliance State:
Set Multimeter to DC Volts 
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure the DC voltage between pin 8 on connector X5 and the earth at the incoming mains supply.
Expect approximately 5 vdc.
Is the voltage measured as expected?
Expect approximately 5 vdc.
Is the voltage measured as expected?
Isolate as per TOPs P4
and refit as necessary