GM-GMC: Lighting Problem, chevy silverado, brake light switch

Question
I have a 2000 Chevy Silverado 160,000 miles with the V-8. My problem is the brake lights wont come on.  The cyclops light does work.  I checked the fuses and brake light switch doesn't seem to be the problem. Need some advice!

Answer
Tami,   
  
 I'm sure you've checked but did not mention if the bulbs in the brk lights have been checked. If OK while they are out it would be a good time to test if there is a 12V signal going to the bulbs as you step on the brks. Also a great time to test for a proper ground also at the bulb/socket. It might be a good idea to have a wiring schematic handy in case you need it. Also if you are using a test light get a long jumper wire and use the Battery(+) and (-) for hooking up you test light I find the grounds around the rear of a truck can be unreliable. Finally if you have no 12V or gound at he socket then you problem is probably in the wiring from the Brk light switch to the back of the truck. If you have a trailer wiring connector this would be a good place to start look for any green/corroded connectors, exposed wiring or broken grounds, these connectors are often installed by inexperienced persons with cheap connectors. hope this helps....let me know how you make out!