Set Appliance State:

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

Measurement:

Test 1.
Measure for resistance across the outer terminals of the gas valve.
Expected resistance approximately 4.4 Kohms.
Note.
Ensure a good connection is made or misdiagnosis will occur.
Test 2.
Measure for resistance across one of the outer terminals & center terminal of the gas valve.
Expected resistance greater than 1 Mohm.
Note.
Ensure a good connection is made or misdiagnosis will occur.