Turn Signal Problem

well there has been an intermittant problem with the left turn signal on my 84 caprice classic.
i'm at college and my dad is trying to fix it, so the details are a little sketchy but here goes.
he replaced the bulb with one that was identical (so he says) and the flasher worked, but it flashed slower on the left side. the right side was still fine.
he was driving it tonight and when he turned the headlights on, the turn signal stopped flashing.

i dont really know all the details, but as i understand the flasher system, it works off a specific resistance value. you cant put HD bulbs in a normal flasher relay and vice versa. why would the system stop working when the headlights come on only?

the bulb he put in is one that he found in the glove box in a napa box. i dont know where the bulb came from, as it was already there when i bought the car. he says its identical to the other bulbs, so i'll have to take his word for it.

thanks for any help.


:popcorn:
ive always wanted to use that

anybody have any ideas?
i need some help with this.

That sounds typical of a poor ground at the headlamp housing and that turn signal

well that could be it. i neglected to mention that this isnt a new problem exactly

it showed up a while ago and i fixed it by putting in a new turn signal bulb.
the old one was corroded and nasty looking.
i put some dielectric grease on to keep water and such out.

the bulb my dad found was either the extra one from the pack i used, or one that he found somewhere else.
i dont think it was from somewhere else now that i think about it, as i remember throwing out a bulb that was in the glove box.

why would the headlight ground suddenly act up?

if it quits when the headlights are on, the bulb itself may be bad. Each turnsignal/parking lamp bulb has two filaments. One dim for the parking lamps, one brighter for the turnsignal/brake lamp. If the brighter filament is burned out, the turn signal will work through the dimmer one unless the headlamps are on. Most (if not all) inop on one side only t/signal issues are bulb or socket related.

Since its only a few bucks, think about changing all the bulbs. I had one bad bulb that LOOKED good but messed up the parkling lights, brake lights. Out of frustration, I changed them all and its been fine ever since. Look at all the sockets and don't use too much of the dielectric grease.

Bob