97 k1500 Rear turn signals and brake lights out, still have running lights, front turns(blink fast like bulb out) also still have third brake light. worked fine one night--next day inop. all bulbs look good-no broken filiment, not cloudy fuses all good. board on back of tail lamp?

 

I have seen bulbs that look good visually but are actually no good. Check them with a meter or try another bulb that you no is good. Also check the sockets for the bulbs, I have seen them get loose and not make a good connection.

 

I HAVE THE SAME PROBLEM. TRIED TO CONNECT LIGHTS TO TRAILER WIRING CUZ CANT FIGURE OUT WHATS WRONG. CHANGED ALL BULBS, CLEAN ALL CONNECTORS, MADE SURE FUSES AND RELAYS WERE GOOD BUT TO NO AVAIL. ANYONE KNO WHAT ELSE COULD BE WRONG? PLS HELP!

 

In both cases if you haven't already, I would inspect the wiring at the drivers side rear corner running up to the back of the tail light...

sounds like something is dead in there. iirc there is a connector there somewhere and you can troubleshoot from there with a test light.

 

My truck blows fuses as fast as I put them in for my turn signals. just started a few weeks ago. I have a new flasher relay, a new turn signal switch and new turn signal relay. checked all my bulbs front and back. Any ideas??? please help lol