help with 12v upgrade problem.

i just recently up graded my 52 pontiac to 12v. all went well except turn signals. first they would flash once then stop so i put in a new flasher. then the outside signals worked correctly but both the dash indicators flash at the same time. i checked grounds at dash and made sure light housings were grounded but no change. i even bought an extra flasher thinking new one was bad.

 

Did you change any wiring when you converted the system?

Is there a "hazard" circuit as well as a turn signal circuit?

Maybe the contacts in the turn signal swirtch are bad/loose allowing a cross conection causing them to both flash at the same time.

Is it an original turn signal system or one that was added on?

What happens when you turn on parking.head lamps and then try the turn signals?

What about when pressing on the brakes so the brake lights are on and then try the turn signals?

 

are you sure the body is grounded try using a jumper cable from the negative battery to a clean bare metal spt on the body and giving it a try

 

did you change any of the blubs?

 

could be that you plugged into the parking light circuit if you disturbed the wiring.

 

wiring is original, yes i changed the bulbs, the blinker system looks to be stock but couldnt find anything in my manual. no hazard circuit. and all the lights and signals work correctly outside of the car no matter what i try and i tried the body ground issue. i was thinking that maybe it was the switch and the conversion just shorted it afterwards. just seeing if anyone else had this prob come up.

 

Changing the voltage wouldn't change the operation as long as you replaced the flasher and bulbs with 12v. Sounds more like a ground issue.

 

I'd trace the wires from the dash indicator back to the switch. My guess is they are touching eachother somewhere along the line causing both of them to light when either turn is made. If you get to the switch and the wiring looks to be ok, then pull the switch out and check it.