I am in the process of wiring in a new oven to replace our 20 yr old one which died last week and noticed that the earth on the cooker control switch is giving a faint glow on the electrical screwdriver. I also noticed that live-out on the switch lights up the neon when the switch is off (though slightly less bright than the glow from earth). What's going on?
You may have a slight leakage on the switch terminals especially if its an old cooker control,they get carboned up and do conduct slightly.
I would change the cooker control and it should solve it.
I have never liked the idea of people using a neon screwdriver or indicator , especially the type where you become part of the circuit under test.
It often does happen that the resistor ( a tiny piece of carbon or similar substance ) is the onlything stopping you taking the whole current,which depending on where you are in relation to the tranformer could end up with +20kA at the terminals or the end of your inicator.