Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove connector M13 from the PCB
Measurement:
Test 1:
Measure the resistance between pin 37 and 38 on connector M13.
Resistance should be approximately as per Table 1.
Test 2:
Measure the resistance between pin 37 and a suitable earth.
Expect a resistance of 1 Mohm or greater.
Are the resistances measured as expected?
Measure the resistance between pin 37 and 38 on connector M13.
Resistance should be approximately as per Table 1.
Test 2:
Measure the resistance between pin 37 and a suitable earth.
Expect a resistance of 1 Mohm or greater.
Are the resistances measured as expected?
Isolate as per TOPs P4
and refit as necessary