Triumph Repair: 1975 Triumph Spitfire 1500, triumph spitfire 1500, test light

Question
My 1975 triumph spitfire 1500 is having problems with the lights.  The brake, reverse, and headlights don't work but the blinkers do.  Any ideas?

Answer
Hi Shelly,
These items are on several different circuits so it is then necessary for you to take a test light and pick only one circuit at a time and trace on a wiring diagram and use the test light to follow the circuit from one end to the other. If you don't have a diagram let me know and I will put one on my web site that you can down load and print.
Howard