Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Disconnect connector X3 from the PCB
Measurement:
Take a measurement of the resistance of your probes as it is critical to this test. It is usually around 2.2 Ohms.
Test 1:
Measure the resistance between pins 4 and 5
(numbered on the connector).
Resistance should be approximately 95 - 130 Ohms.
Test 2:
Measure the resistance between pins 1 and 2.
Resistance should be approximately 3 Ohms.
(i.e. multimeter will display 3 Ohms if the probes have a resistance of 2.2 Ohms)
Test 1:
Measure the resistance between pins 4 and 5
(numbered on the connector).
Resistance should be approximately 95 - 130 Ohms.
Test 2:
Measure the resistance between pins 1 and 2.
Resistance should be approximately 3 Ohms.
(i.e. multimeter will display 3 Ohms if the probes have a resistance of 2.2 Ohms)
Isolate as per TOPs P4
and refit as necessary