Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect plug on the spark generator

Measurement:

Test 1:
Measure the resistance across the L and N
connections on the spark generator.
Resistance should be greater than 1M Ohm.
Test 2:
Measure the resistance across the L connection
on the spark generator and a suitable earth point.
Resistance should be greater than 1M Ohm.