Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Gain access to PCB (use Insulation Mat as required)

Observation:

Check the harness running between the spark generator to X1 / X2 at the PCB is fitted correctly and free from any damage.
Brown = X2 Pin 4
Blue = X1 Pin 2 (shared)
Green/Yellow (Earth) = X2 Pin 2 (shared)
Black = X2 Pin 1.