Re: No headlights on sprite
You should have three different coloured wires on the back of the lighting switch, Red, Blue and Brown with a Blue tracer. The Brown/Blue wire is the feed for the lights which comes from the Voltage control Box. If you can, check the Blue wire becomes live when the switch is set to headlight on position. If ok then check the headlight dip switch. The Blue wire goes from the light switch to the dip switch. The dip switch then sends power to the headlights via Blue/White or Blue/Red wires for main or dipped headlights dependant on setting.
Sounds likely the dip switch is possibly faulty?
This all assumes the car has standard wiring and no relays have been fitted for headlight operation?
Hope this helps and let us know how you get on.