Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove spark generator from gas valve

Measurement:

Test 1. Measure for resistance across the gas valve connections.
Expected resistance approximately as per table below:
Test 2. Measure for resistance across the gas valve connection and a suitable earth connection.
Expected resistance as per table below: