light

I wonder if anybody can tell me what the redlight is for under the dash on a 405.the light lense is by the steering wheel about knee hight,there is two wires coming from it but i have never took the trouble to follow the wires to find out where they go.the car dos not have a tow bar and never had.so i dont know what this red light is for.. any help please. from chris Addlestone Surrey