Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Disconnect connector ST1 from PCB
Measurement:
Test 1: Measure the resistance across the connections of disconnected connector ST1.
(Ensure good connections are made).
Expected resistance readings should conform to the table below:
Test 2: Measure the resistance between
the black wire to a suitable earth point.
Resistance should be greater than 1M Ohm.
(Ensure good connections are made).
Expected resistance readings should conform to the table below:
| Leads | Resistance in Ohms | Black - Red | (Approximately) 64 ohms |
| Black - White | (Approximately) 95 ohms |
Test 2: Measure the resistance between
the black wire to a suitable earth point.
Resistance should be greater than 1M Ohm.
Isolate as per TOPs P4
and refit as necessary