Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect the gas valve connector from the pcb
(3-pin connector)

Measurement:

Measure for continuity between the leads listed below.
The resistance should conform to the table below:
LeadsResistance
Blue - BlueContinuity
(zero resistance)
Orange - Orange Continuity
(zero resistance)