Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Disconnect spark generator from gas valve
Measurement:
Test 1:
Measure resistance across pin 1 and pin 3 on the gas valve (expected resistance approximately 6.5 kOhms).
Test 2:
Measure resistance across pin 1 and pin 4 (expected resistance approximately 7.4 kOhms).
Measure resistance across pin 1 and pin 3 on the gas valve (expected resistance approximately 6.5 kOhms).
Test 2:
Measure resistance across pin 1 and pin 4 (expected resistance approximately 7.4 kOhms).
Isolate as per TOPs P4
and refit as necessary