Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove the cover from the ignition control box
Remove the 12 pin connector

Measurement:

Measure the resistance between pins 5 (red) and pin 7 (black) on the connector.
Expect short circuit/zero resistance.
Is the resistance measured as expected?