Electrical nightmares 68 tbird

[jon774]

No brake lights, turn signals or rear running lights. I have power all the way up to the sockets then I plug in the new bulb...nothing. The test light will blink out the sequence on the turn through the socket but once the bulb is in nothing. That's the case for all rear sockets and front turn sockets
Just bought a brand new modern sequential unit from Cougars Unlimited and it didn't solve the issue. Any ideas? I have headlights.

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[jazbo]

No brake lights, turn signals or rear running lights. I have power all the way up to the sockets then I plug in the new bulb...nothing. The test light will blink out the sequence on the turn through the socket but once the bulb is in nothing. That's the case for all rear sockets and front turn sockets
Just bought a brand new modern sequential unit from Cougars Unlimited and it didn't solve the issue. Any ideas? I have headlights.

I'd start checking the ground return path. Try jumpering the negative side of the bulbs and or the sequential unit to a good ground point on the frame.

If you have a service manual the schematic seection should help.

 

[jon774]

Ok interesting fact, the bezel needs to be on the car for the sequentials to work, must be a grounding connection between socket and bezel metal. Still no brake or running lights. Checking all grounds... Again

 

[OneAmongOthers]

I got the wiring schematics if you need anything. Though its for a 69, but it might help. I can photo copy stuff. Also did you try replacing the flasher can? Check the fuses? The 1968 tbirds also used the older mechanical sequencer not the solid state one. Maybe you are having an issue there? My issues with lights not flashing was the flasher can itself.

 

[jon774]

I got the wiring schematics if you need anything. Though its for a 69, but it might help. I can photo copy stuff. Also did you try replacing the flasher can? Check the fuses? The 1968 tbirds also used the older mechanical sequencer not the solid state one. Maybe you are having an issue there? My issues with lights not flashing was the flasher can itself.

It was the bezel not being attached that was the problem with the sequentials, flasher and running lights. The brake lights were a skewed switch in the brake pedal that needed to be taken out and reset. So all the rear lights work now! The only issue now is the front turning lights but I have a feeling that if I installed the fixture in place they would work.
Thanks for all the responses. It certainly helps getting more insight than just the voices in my head.

 

[OneAmongOthers]

These era Thunderbird had a weird feature for the front turn signals. Well at least the 1969 did... Not sure if the others did because I believe the other cars had a solid front bumper with the turn signals in them. The 69 had only a partial front bumper with a lower front valence. The turn signals were housed in individual housings. Anyway... If the same is true for all the cars what happens is when you bring on the parking lights all marker lights come on. Front, side and rear. Now when you pull the switch to bring on the headlights the front turn signals would shut off so only the head lights are on. A little feature carried over from the previous generation of Thunderbird. The turn signals should still work normally when you click them on respectively. I guess they only wanted the headlights to be on.

EDIT FUN FACT: Did you know that up until like the 70's Thunderbird was not a Ford product but a line in itself? Yup! If you ever watch old Thunderbird commercials from the 50's to late 60's they always said something like "New from Thunderbird!" Or "There's a new Thunderbird!" Ford really did hold Thunderbird in high regard for quite some time. Also ALL Thunderbirds were built only at the Wixom plant as well. Well that's enough of my rambling...

 

[Excaliburss]

Congrats ! It is always a good feeling when things come back as they should.

 

[Excaliburss]

Would you mind posting a picture of the "bezel" you are talking about. I really do not remember any bezel on my 68.

 

[OneAmongOthers]

Would you mind posting a picture of the "bezel" you are talking about. I really do not remember any bezel on my 68.

I think he means the part that holds the tail light assembly. That black metal part.

 

[Excaliburss]

Then the whole thing should be loose......? 🙁 I had mine out once and there a lots of screws..... But that should not be the issue here as the bulbs get both neg/pos. thrue the cables

 

[jon774]

The first pics the back of the bezel. Most of the sockets need to be in contact with that before all the light will work. The second pic shows it's entirety from the back it's integrated into the rear lens

 

[jon774]

The first pics the back of the bezel. Most of the sockets need to be in contact with that before all the light will work. The second pic shows it's entirety from the back it's integrated into the rear lens

Couple more pics

 

[Excaliburss]

Thanks a lot, makes us understand the problem better. Looks like your car has the same color as mine !