Set Appliance State:

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

Measurement:

Test 1:
Measure the resistance between pin 8 (grey) and pin 9 (blue) on the ignition control box connector.
Expect a resistance of between 25 and 50 ohms.
Test 2:
Measure the resistance between pin 8 (grey) and a suitable earth.
Expect a resistance of 1 Mohm or greater.
(O.L is acceptable because this is greater than 1Mohm)
Are the resistances measured as expected?