hi guys im new here so please be gentle lol

ok i have 2001 escort 55 van great little van but had a few problems when i brought it one being the dreaded heater matrix not working , ok so after reading on here about how much of a pig it was to change i thought id give it a go , when removing the steering wheel there is a disc behind the wheel with a gold in coulour loooooooong wire which is attached to the steering wheel and ive broke it so my question is ,

what is this ??
and
what does it do ?

thanks in advance , stu