79 Turn signal problems
Burning Brakes
Joined: Nov 2013
Posts: 889
Likes: 13
From: Jax/St. Augustine FL
I had same issue on my 81 and it turned out to be this:
Combination of hazard fuse and turn signal fuse AND making sure all "blinking" bulbs were 1157 and Only the reverse were 1156
I also replaced my turn signal switch in the column but only when I replaced the hazard fuse did my turn signals work with lights on....and yea very odd that my hazards always worked...
Try replacing your hazard fuse it's 5 bucks at autozone
Combination of hazard fuse and turn signal fuse AND making sure all "blinking" bulbs were 1157 and Only the reverse were 1156
I also replaced my turn signal switch in the column but only when I replaced the hazard fuse did my turn signals work with lights on....and yea very odd that my hazards always worked...
Try replacing your hazard fuse it's 5 bucks at autozone
Cruising
Joined: Dec 2013
Posts: 12
Likes: 0
Thank you DUB for pushing me to look for a bad ground before installing a new Headlight switch. I did find a bad ground in one of my rear sockets. The suggestion to pull all lights and work with one socket and a tester at a time did the trick. All my lights now work as designed. 
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Thank you DUB for pushing me to look for a bad ground before installing a new Headlight switch. I did find a bad ground in one of my rear sockets. The suggestion to pull all lights and work with one socket and a tester at a time did the trick. All my lights now work as designed.
DUB
Intermediate
Joined: Apr 2013
Posts: 26
Likes: 0
From: Spring TX
Fixed! Thanks!!!
IF you have turn signals working when you use them with NO HEADLIGHTS ON...GREAT.
BUT...if when you go and turn your headlights ON...and ALL the appropriate lights come on when you do so...and try to use your turn signals and they do not work...you have GROUND PROBLEM! Usually in the socket(s)..but not always.
The reason your turn signals are working when the headlights are OFF is because...the turn signals are using the un-used filament in the bulb (1157)...and getting the ground through that filament....which is your driving/park light filaments in the bulb...BUT...when you turn your headlights ON....that filament is being used....and it is working BECAUSE it is finding a GROUND through your filament for your turn signals....SO..when you try to use your turn signals...there is NO GROUND...because you actually have NO GROUND getting to the section of the socket that grounds the brass section of the bulb.
I have also had to get into columns to replace turn signal switches due to "BOZO" got int there and messed it all up. I usually just plug in the turn signal switch connector at the base of the column and do all my testing BEFORE I actually install it.
Brake light, turn signals and hazards ALL use the same filament in the bulb. Driving,running light use other filament.
DUB
BUT...if when you go and turn your headlights ON...and ALL the appropriate lights come on when you do so...and try to use your turn signals and they do not work...you have GROUND PROBLEM! Usually in the socket(s)..but not always.
The reason your turn signals are working when the headlights are OFF is because...the turn signals are using the un-used filament in the bulb (1157)...and getting the ground through that filament....which is your driving/park light filaments in the bulb...BUT...when you turn your headlights ON....that filament is being used....and it is working BECAUSE it is finding a GROUND through your filament for your turn signals....SO..when you try to use your turn signals...there is NO GROUND...because you actually have NO GROUND getting to the section of the socket that grounds the brass section of the bulb.
I have also had to get into columns to replace turn signal switches due to "BOZO" got int there and messed it all up. I usually just plug in the turn signal switch connector at the base of the column and do all my testing BEFORE I actually install it.
Brake light, turn signals and hazards ALL use the same filament in the bulb. Driving,running light use other filament.
DUB
2nd Gear
Joined: Jun 2019
Posts: 2
Likes: 0
Having trouble with the turn signals on this 78. when switched to the right nothing works but the front right indicator. when switched to the right side both rear light come on ( nothing in the front) and
doesn't do a damn thang with the head lights on. replaced both flashers and the turnsignal switch plz help before i use car for target practice
doesn't do a damn thang with the head lights on. replaced both flashers and the turnsignal switch plz help before i use car for target practice
