Brake lights and turn signals

I'm a newby to this forum but have a problem with my truck. Recently my left turn signal dash light started flashing rapidly when turned on. About a week later the same happened to the right. When I investigated, I found that though the bulbs were ok, I had neither rear turn signals or brake lights. Front turn signals work, four ways (hazard lights) do not. Ideas? solutions?

What year is your truck.
Without all the information its difficult to give accurate replies.
Most likely the rear circuit boards are defective, but that is just a guess.

Thanks GMMerlin,
My truck is a '98 4X4 K1500 Sierra.

Hey Hollandp,
Did you get this problem fixid yet? let me know if not as I had the same problem.

Hey Hollandp,
Did you get this problem fixid yet? let me know if not as I had the same problem.


Melaman,
No, I have not figured out the problem. Hope you have the fix!
Thanks for the reply.

first check the wiring to the lights, start at the lights and work your way back the harness may be unpluged or have broken wires. if the wires are good then it's the multifunction switch(signal etc.) try banging on the tob of the steering column by the hazard switch and see if everything starts working. burnt out bulbs or broken wires make the signals flash realy fast. the brake lights go through that multifuntion switch as well they go bad all the time. check the fuses before you get too caried away. good luck

I had the same problem recently with my 99 GMC Sierra 1500. The right blinker started blinking rapidly one day. I changed out the bulb (mine actually had burned out), but 5 minutes later, the rapid blinking started again and again no brake light or turn signal.

I took the tail light socket assembly into the parts dept of the GM dealership. After the parts guys looked at it, he told me this:

Where the bulb plugs into, there is this paste-like substance that the factory puts into the sockets that is used to prevent the effects of moisture on the metal connectors of both the socket and the bulb. I forget what he called this stuff, but besides its purpose to prevent moisture in the socket, it is also electro-conductive so that the bulb gets juice from the socket. Well, this is ok until the substance dries out.

So, in my case, this stuff was dried to the point of being clay-like and the bulbs were not making a good connection in the socket. You need to scrape out that stuff from the metal connectors in the sockets. Be sure to disconnect the wires from the tail light socket assembly first, as you will probably use something metal to scrape out the dried goop and you don't want to short anything. I used a thin nail, but what would probably work better is a dental scraping type tool. You can get them at a hardware store or Home Depot.

I will also add that I live in Arizona, where it is very dry, not much rain. So, that moisture paste stuff I don't really need. If you live in an area that rains or snows alot, or you live on the coast, my solution may work temporarily until moisture has it's way with the sockets! Maybe a new tail light socket assembly might be the best bet...

Good luck!

SunDog67
1999 GMC Sierra 1500 Ext. Cab 305 (5.0 Litre)