Hello everyone, it has been a few months since i have been on TGO but i am home for spring break from college. I came home to fix some odds and ends on my firebird so that i may take it back up to school with me. Last fall i swapped my 83 TA bar-style taillights for the 89 formula style taillights.
I ran into the issues with the existing harness having different lighting priorities for the different bulbs and different style sockets for the bulbs. So i went out and got a functional formula harness i replaced the bulbs checked the fuses in the car and replaced the flasher for the hell of it. I had the harness working in the bench with my 12v power supply. Yesterday when i installed it into the car every function of the taillights functioned properly with the exception of the brake lamps.When i stepped on the brake pedal the left rear turn signal illuminated only. I was having problems like this last fall with it and gave up before i went away to school. I am at my wits end with probing wires and checking resistances. I need some help on this one.

P.S. Last summer i installed a 355 vortec with a fresh 700r4. I have probably put like 40 miles on the new engine/tranny since its been installed and its just sitting in my driveway. This is the last issue that needs to be worked out so that i can finally get it in the road. I appreciate any and all help/insight given.
Thanks -Bob

 

Well after some toying today i have found that the independant brake/turn function in the tail lights is not working properly. It seems as though when the brake pedal is depressed the brake lamp wiring sends power to the turn signals as to signal a stop pattern. Does anyone know the trick that eliminates the brake and turn signal as one, making the turn signals independant of the brake lamps. I have been searching for a post i read from 2 years ago giving detailed instructions of how to make the turn signals independant from the brake circuit while using the existing 85 front harness. I believe that it said to cut one wire from a turn/brake relay circuit then to splice that to the rear brake lamp circuit. If anyone knows how to do this please help! Thanks, -Bob

 

Are you using dual element bulbs in there?

 

Yes, i believe that they are 1156's

edit: in the brake lamp sockets yes, they are dual elements, in the turn signals they are single element bulbs

 

it should be dual element in the turn signal lights as well.

 

Thanks Trickster, when i get home i will try them out. Thats interesting, because when i picked up the tailights from my friend they still had the sockets from the harness in them. The turn signals had single element bulbs in them. I just assumed that they required single emement bulbs. -Bob

 

The turn signal bulbs are single element, and the sockets for them are single element. The problem is that when braking, power is given to the turn signals because in the old harness the brake lamps and the turn signals were integrated as dual function lights. I need to know how to make the brake lamp funtion seperate from the turn signal function.Thanks -Bob

 

Well after few hours of testing and probing i found that i did not properly disable the relay that controls the turn/brake priority. Also my test light had a bad cord and was inop at times. I modified the relay circuit and installed the correct bulbs in the sockets (dual element in the brakes and single for the turns/reverse). I finally got the tailights to work properly. -Bob