Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove connector 54/11 from the PCB

Measurement:

Measure the resistance between the blue, black and brown wires on connector 54/11 to the corresponding leads 1, 2 and 4 on the spark generator.
Expect continuity / zero resistance on each test.
Also visually inspect the condition of the harness.