The Tbird is finally done and going to trailer to my daughter next weekend.  An issue cropped up.  I replaced all the wiring, switches etc as part of the restoration project.  Brake lights and turn signals were working fine all of a sudden, when I turn on a turn signal they don't work but brake lights work just fine as do head lights.  If I step on the brakes and then switch on the turn signal the brake light goes out on that side but does not blink. Same issue both sides.  Once I turn off the turn signal the brake light comes back on just fine.  I am hoping its the flasher and not the signal.  Thoughts?

I appreciate all the help over the years.  The car runs great after sitting since 1967. 

Rexbd,

GROUNDING, connections, other "push-ons" & turn signal switch all come to mind.  Unlike modern vehicles, these older ones depend on good chassis grounding for the return path for most circuits.  Grounding is highly suspect, followed by the various connections, light sockets, lightbulbs, etc.

Easiest to check bulbs first, then bulb sockets; and, with a helper, voltage to the bulb from the BATTERY ground connection (NOT the chassis - you'll need a long wire to reach from the battery ground back to where you're working).  If those all check out, then it is 99+% likely a grounding issue.

Good luck!!  Those are sometimes the worst "troubleshooting" to do.

Regards, JLB




55 Ford Crown Victoria Steel Top

Forget it!!  I misread your symptoms.

More likely the flasher since the brake lights work and go out when turn signal switch is engaged.

Regards, JLB

55 Ford Crown Victoria Steel Top

Happened to me. Check the inline fuse to the Flasher, it's not the one behind the light switch.
 If you do not have a schematic of your car look up "Classic Car Wiring" on the net. For $18 i received from them a 11" x 17" laminated wiring diagram of my 56 Ford with all the stock wire colors. It has been invaluable in trouble shooting my car.  

56 Vic, B'Ville 200 MPH Club Member, So Cal.

I agree that it maybe a bad flasher or maybe one of the wires came off the flasher.  The fact that the stop light goes out when the turn signal is operated means the circuit is probably ok.  But just in case, check the grounds to all four lights with a temporary ground but if there was a poor ground to a housing than you would probably have more problems than just the signal light.




54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

I second that suggestion regarding the Wiring Diagram.I bought One and my Buddy was so impressed He asked Me to get Him One. The  Wires shown in the Diagram are the actual Colors of the Wiring. Use that Diagram and your Shop Manual to diagnose most Electrical Problems. They also make a larger Size than 11 x 17.

  

I also bought one of those diagrams and it is great. The wire colors is most helpful. I had a not uncommon problem of the front parking lights coming on with the brakes. By following the diagram it is now fixed. Those little 6 wire connectors can be a beast once the wires are removed!



Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

I expand on my find. It happened when I had removed everything for a media blast and repaint of the entire car. I was reinstalling everything with new gaskets and tested as I went. Suddenly everything went goofy. I ended up adding a ground to each part. Nothing worked. I decided to check the flasher and found the fuse was good but not making contact. Changed the inline fuse holder and everything worked as normal. I needed no added grounds. I found the fuse because of the drawing. I wish Ford would have had a fuse block in 56.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Actually I added a fuse box behind the left lower dash on mine. 

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire