Parkinson Cowan 60 GLXA Main oven Auto ignition not working

My Parkinson Cowan 60 GLXA has developed a fault on the main oven. Basically it appears the auto ignition has ceased to work and blown the 3amp fuse. i have replaced the fuse and checked the clock comes back on, i checked the manual ignition for both the burners and the grill/2nd oven and that works fine. As soon as i turn the main oven on the fuse blows. Can you advise me what is likely to be faulty and which part will need to be replaced, that’s assuming the fault can be fixed