Turn signals / brake lights not working on '66.

J

jonnymb_98

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May 22, 2019
Thunderbird Year
1966
Trying to resolve a host of electrical issues with my '66 Thunderbird. Not very inclined with this sort of stuff, so if my information is insufficient then please let me know and I will try to oblige.

Initially, none of the turn signals or brake lights were functioning. I replaced some fuses, then voila, the right turn signal was working. And the brake lights were working IF the right turn signal was active, and only then... lol.

Few minutes ago, went to replace the top right fuse, realized I didn't have a replacement so I put it back in, and now none of the turn signals and brake lights are working.

Any ideas at all? Ty.



Edit:

Note that the headlights and tail lights (last I checked) worked properly.
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Maybe get some circuit cleaner and remove some of the green crustys. Do you have a multi-meter or a test probe?
 
jonnymb_98 said:
Trying to resolve a host of electrical issues with my '66 Thunderbird. Not very inclined with this sort of stuff, so if my information is insufficient then please let me know and I will try to oblige.

Initially, none of the turn signals or brake lights were functioning. I replaced some fuses, then voila, the right turn signal was working. And the brake lights were working IF the right turn signal was active, and only then... lol.

Few minutes ago, went to replace the top right fuse, realized I didn't have a replacement so I put it back in, and now none of the turn signals and brake lights are working.

Any ideas at all? Ty.

Couldn't attach all photos, so here's an album.

https://*********/a/8BVjmVD

Edit:

Note that the headlights and tail lights (last I checked) worked properly.
Click to expand...



By the pictures you up-loaded, you have a lot of corrosion on almost all connections and bulbs. One of the most critical things on these old 'birds is the ground. I would suggest running another ground wire, #8 AWG with lugs on both ends, attach one to the negative terminal on your battery, and the other to a good, clean, bolt/post on the frame/body.
Then, you need to clean all the bulb sockets, and ground connections, usually a black wire that may be common to multiple sockets, and eventually to a ground terminal. Check and clean, tighten all the ground connections you can find, including the relays in the trunk, where they bolt to the body. You will find that a good solid ground will help with almost everything on the car, the window motors should run faster, headlights and interior lamps will be brighter, and and the horn may actually be louder.
Cheers
 
Great Advice Poppy Red!!.. JonnyMB always do those simple things first just like Poppy Red Suggested..
 
Hey Dj-Dan, what do you mean by green crusties?

Poppy Red, ty for that information, I will try that immediately. How would you suggest cleaning the bulb sockets and ground connections? Like I said, novice to this completely.
 
jonnymb_98 said:
Hey Dj-Dan, what do you mean by green crusties?

Poppy Red, ty for that information, I will try that immediately. How would you suggest cleaning the bulb sockets and ground connections? Like I said, novice to this completely.
Click to expand...


For the bulb sockets, after removing the bulbs, spray a cleaner into the socket. Electrical cleaner/spray will work, or a cheaper solution is WD 40. It is more oily that electrical cleaner, but is is a kind of loosen-all fluid and will help with dirt, crud, etc. Get a small wire brush, round bottle cleaner type, or something that you can get into the sockets ,go around and round the inside of the socket, and then blow it out with compressed air, (if you have access to an air compressor). Make sure the center silver contact is clean, and the contact moves in and out, showing that the spring is not seized. Same thing with the bulbs. clean the outer shell, particularly where the bayonet pins are, and the center contact.
Ground connections are the easiest. Use a small wire brush, (or brass), to clean the terminals if it has one, or, in some extreme cases, use a fine-cut file to get a good, shiny surface on both sides of the terminal. Also, make sure the screw and/or hole in the body where the ground is attaches, is clean, scrape a little paint off, if necessary.

Your main fuse block under the dash on the passenger side kick panel is in bad shape. I would disconnect the battery, remove all the fuses, and spray the crap out of it with WD40 to start. It will help loosen some of the rust and "green crusties"! Then, again, with a small wire or brass brush, clean all the terminals, fuse section dividers and so on. Give the nuts of the larger supply wires (top ones) a good brush cleaning. You might loosen/remove one of the nuts, remove the wire to see if it is clean underneath. If it is, then you probably do not have to remove all of them and clean the ring terminals. Then give the complete fuse block a good spray clean with electrical cleaner to remove any WD40 and let it dry properly.
I hope you have a lot of patience, because you should also pull apart any of the 2, 3 or 4 wire connectors, spray them with WD40, and then connect, disconnect and reconnect them a few times to get the matching pins clean. the WD 40 won't hurt them ad will eventually evaporate.
Lastly, check your fuses with an ohmeter/multimeter, or some type of continuity tester. Sometimes a fuse looks good to the eye, but is not making contact at the end terminals and can give you a fits.

Good luck. Cheers
 
Green crustys is copper oxidation. There is no electrical contact when there is green or rusty/white on the contacts. It needs to be removed so you have a good electrical contact .
 
Dj-Dan said:
Green crustys is copper oxidation. There is no electrical contact when there is green or rusty/white on the contacts. It needs to be removed so you have a good electrical contact .
Click to expand...
Dan, I couldn't resist looking up the definition of "crustys". You can't make this stuff up!

"Anyone or anything that is ugly, raggedy,, slump or cheap. 'Don't look at me with yo crusty ass!'"

Green crustys? I can't even imagine...

Cheers,

Doug
 
If you ever want to hear about car repair SMA (South Main Auto), on youtube. This guy is Fantastic on all kinds of modern car repair . I got the phrase "the green crustys" from him. He has names and phrases for all kinds of things he uses or sees. I have fixed many many cars through his videos. A real down to earth guy (Eric O).
 
Poppy Red said:
For the bulb sockets, after removing the bulbs, spray a cleaner into the socket. Electrical cleaner/spray will work, or a cheaper solution is WD 40. It is more oily that electrical cleaner, but is is a kind of loosen-all fluid and will help with dirt, crud, etc. Get a small wire brush, round bottle cleaner type, or something that you can get into the sockets ,go around and round the inside of the socket, and then blow it out with compressed air, (if you have access to an air compressor). Make sure the center silver contact is clean, and the contact moves in and out, showing that the spring is not seized. Same thing with the bulbs. clean the outer shell, particularly where the bayonet pins are, and the center contact.
Ground connections are the easiest. Use a small wire brush, (or brass), to clean the terminals if it has one, or, in some extreme cases, use a fine-cut file to get a good, shiny surface on both sides of the terminal. Also, make sure the screw and/or hole in the body where the ground is attaches, is clean, scrape a little paint off, if necessary.

Your main fuse block under the dash on the passenger side kick panel is in bad shape. I would disconnect the battery, remove all the fuses, and spray the crap out of it with WD40 to start. It will help loosen some of the rust and "green crusties"! Then, again, with a small wire or brass brush, clean all the terminals, fuse section dividers and so on. Give the nuts of the larger supply wires (top ones) a good brush cleaning. You might loosen/remove one of the nuts, remove the wire to see if it is clean underneath. If it is, then you probably do not have to remove all of them and clean the ring terminals. Then give the complete fuse block a good spray clean with electrical cleaner to remove any WD40 and let it dry properly.
I hope you have a lot of patience, because you should also pull apart any of the 2, 3 or 4 wire connectors, spray them with WD40, and then connect, disconnect and reconnect them a few times to get the matching pins clean. the WD 40 won't hurt them ad will eventually evaporate.
Lastly, check your fuses with an ohmeter/multimeter, or some type of continuity tester. Sometimes a fuse looks good to the eye, but is not making contact at the end terminals and can give you a fits.

Good luck. Cheers
Click to expand...
I would also recommend disconnecting the battery before you stick a wire brush into the light sockets. You could cause a direct connection to ground and blow fuses or start melting wires / connections. If I remember correctly the '66 Thunderbird has metal light sockets which act as ground when snapped into place in the tailight assembly.
 
Good news (I think). All I've done is take a brush and electrical cleaner to the bulb sockets and tail light connectors. Replaced a fuse.

Left and right blinkers are now working, as well as the front blinker indicators (not sure what they are called). The far right bulb in the back does not turn on for the right blinker, but it does turn on when the headlights are activated. The brake lights still are not functioning at all (bad brake switch?). Reverse lights aren't working either.

Any ideas?

Edit: I still plan on attempting to run another ground wire, just doing my diligence with research because I'm very new to all of this.
 
jonnymb_98 said:
Good news (I think). All I've done is take a brush and electrical cleaner to the bulb sockets and tail light connectors. Replaced a fuse.

Left and right blinkers are now working, as well as the front blinker indicators (not sure what they are called). The far right bulb in the back does not turn on for the right blinker, but it does turn on when the headlights are activated. The brake lights still are not functioning at all (bad brake switch?). Reverse lights aren't working either.

Any ideas?

Edit: I still plan on attempting to run another ground wire, just doing my diligence with research because I'm very new to all of this.
Click to expand...

The lights at the back of the car are dual filament. One filament in the bulb is for taillights (when you turn on parking or headlights) the other filament is for brake / directional. You probably need to replace that bulb.


If all stop lights do not operate, the problem can be at the stop light switch, Stop Light Relay, Turn Signal Relay or the wires between the three components may be open.
Test for power across the Stop Light Switch terminals with the Brake Pedal depressed. If there is no power, the Stop Light Switch is defective. If there is power, test for power at the Stop Light Relay to determine if it has a good ground connection and if it is operating. If there is no power, there is a defect in the wiring between the Stop Light Switch and the Stop Light Relay. If there is power and the relay is functional, check the wire and connections between the Stop Light Relay and the Turn Signal Relay. If the wire is good, there is a defective connection inside the Turn Signal Relay.

The back up lights are switched at the neutral safety / back up switch. You should check there to see if there is power. It could be a bad fuse. I know on earlier year (64) the same fuse is used for the windshield washer. I was able to verify from the diagrams that yes, the washer and back up lights are the same fuse in the fuse box on the 66. Does your washer work? If not most likely need to replace that fuse and insure a good connection there in the fuse box. I'm looking at the 66 wiring diagrams to try to figure out the circuits.
 
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I will troubleshoot those things when I can, thank you.

However the bulbs I'm using are brand new.
 
jonnymb_98 said:
Where are those located btw, under the dash?
Click to expand...
If you're asking about the fuse the fuse box is on the passenger side behind the kick panel.

If you're asking about the neutral safety start switch my guess is that it's on the steering column under the dash.

I'm pretty sure the stop light switch is hydraulic and is mounted on or near the master cylinder.

I'm not sure about the stop light relay but I think that is mounted on the side of the fender possibly behind the windshield washer bag.
 
Poppy Red said:
For the bulb sockets, after removing the bulbs, spray a cleaner into the socket. Electrical cleaner/spray will work, or a cheaper solution is WD 40. It is more oily that electrical cleaner, but is is a kind of loosen-all fluid and will help with dirt, crud, etc. Get a small wire brush, round bottle cleaner type, or something that you can get into the sockets ,go around and round the inside of the socket, and then blow it out with compressed air, (if you have access to an air compressor). Make sure the center silver contact is clean, and the contact moves in and out, showing that the spring is not seized. Same thing with the bulbs. clean the outer shell, particularly where the bayonet pins are, and the center contact.
Ground connections are the easiest. Use a small wire brush, (or brass), to clean the terminals if it has one, or, in some extreme cases, use a fine-cut file to get a good, shiny surface on both sides of the terminal. Also, make sure the screw and/or hole in the body where the ground is attaches, is clean, scrape a little paint off, if necessary.

Your main fuse block under the dash on the passenger side kick panel is in bad shape. I would disconnect the battery, remove all the fuses, and spray the crap out of it with WD40 to start. It will help loosen some of the rust and "green crusties"! Then, again, with a small wire or brass brush, clean all the terminals, fuse section dividers and so on. Give the nuts of the larger supply wires (top ones) a good brush cleaning. You might loosen/remove one of the nuts, remove the wire to see if it is clean underneath. If it is, then you probably do not have to remove all of them and clean the ring terminals. Then give the complete fuse block a good spray clean with electrical cleaner to remove any WD40 and let it dry properly.
I hope you have a lot of patience, because you should also pull apart any of the 2, 3 or 4 wire connectors, spray them with WD40, and then connect, disconnect and reconnect them a few times to get the matching pins clean. the WD 40 won't hurt them ad will eventually evaporate.
Lastly, check your fuses with an ohmeter/multimeter, or some type of continuity tester. Sometimes a fuse looks good to the eye, but is not making contact at the end terminals and can give you a fits.

Good luck. Cheers
Click to expand...
Do as these guy's say. That was always the problem on my 56 Ford WAY BACK in high school, 1966
 
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