Indesit PI 640

Question

When *I connect the spade connectors of the warning light to the terminals of the bank of switches, the light remains illuminated until i isolate the power supply to the appliance. The users guide says that the warning light will illuminate when one of the hobs is switched on, which suggests to me that it is energised by one of the switch terminals. I stand to be corrected on this. I am unable to extinguish the light by turning off all the plate switches. This is what is confusing me. I have tried leaving the light on for a few hours and have returned to find the light still on.
The hob is brand new so I feel that it is a wiring fault of mine.