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Discussion Starter #1
Hello I am a 21 year old working to get a 1966 auto 289 coupe back up and running. The car has been great mechanically but the wiring like most of these cars is a basket case. I have no lights in the dash, no flashing indicators, and no tail lights. The only way I know they have power is because I turn on the headlights and the taillights stay on. I have replaced the neutral safety switch, all fuses and the turn signal switch but cannot figure out what is going on. Any help would be greatly appreciated, Thank you.
 

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Welcome to VMF ! Start simple and be sure the bulbs are good on both elements. One part of your post says you have no tail lights and one part says you do...
 

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Discussion Starter #4
Sorry! For more clarification I do not have reverse lights, brake lights or turn signals, but I do have the running lights.
 

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1) Make sure you are not using LEDS, and make sure the bulb is new. NO LEDS. You're 55 year old wiring is not setup for LEDS.
2) Check bulb sockets for corrosion. No corrosion allowed in the socket. It should shine.
3) Check in the trunk for wiring corrosion and bad wiring behind the taillight. Get a light continuity tester and work from there back twords the dash.
4) Don't try to solve them all at the same time. Pick one of the lights that's not working, and fix that one before you move on to the other. Much less frustration.

Make sure the - Terminal of your battery is removed before you go poking around in the electrical.
 

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I just fixed the reverse lights on mine today. The bulb sockets were corroded. Use a pick to clean the bulb channels, then some Scotch Brite pad and screwdriver.
 

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Okay....

Power for the brake lights comes from the headlamp switch (believe it or not) then proceeds to the stop lamp switch on the brake pedal, then up the steering column to the turn signal switch, back down the column and out through the left kick panel, through a channel under the driver's door sill plate and up the left side of the car into the trunk.

Power for the turn signals comes by way of the ignition switch to the turn signal flasher then up the steering column to the turn signal switch. When leaving the turn signal switch it uses the same "output" as the brake lights as they use the same filament in the rear bulbs for both brake lights and turn signals (the turn signal switch actually "interrupts" the brake lights when the switch is selected for a particular side).

Typically, when you have NEITHER stop lights NOR turn signals the problem can be traced back to the turn signal switch, the wires leading from it back to the rear of the car, the lamp sockets or bulbs, or grounds.

The first place to check is for power at the stop light switch. Disconnect the plug and using a test light probe the pins in the plug. One should have 12V. The other should have nothing. If you don't have any power at either pin you need to trace the wire back to the headlight switch but I doubt you'll find that to be the issue.

The next place to check is for power at the turn signal flasher. Disconnect the plug and check the pins of the plug for power. Again, one should have 12V and the other nothing. If you don't have power at either pin you need to trace the wire back to the splice with the ignition switch "A" circuit. Again, I don't suspect the problem to be there, either.

Next, examine the connector for the steering column harness to make sure it's secure. You can use a small cotter pin or unbent paper clip and your test light to "backprobe", that is to slip the "tool" into the connector from the side where the wires enter the plug so you can check for power while leaving the connector sides plugged into each other. The brake lights should be the solid GREEN wire in the connector. The turn signals should be the solid BLUE wire. The GREEN wire should have power whenever you depress the brake pedal. To isolate the switch, use another small cotter pin, etc., as a jumper to connect the pins in the stop light switch plug. This should provide constant power to the GREEN wire regardless of whether the pedal is depressed or not. If you had power at the stop light switch in the initial test, have jumpered the stop light switch plug, and DON'T have power to the GREEN wire at the steering column harness connector then you have a wiring issue between the stop light switch and the steering column harness connector.

Now, turn the ignition switch to the "ACCY" position. You can also use the "ON" position, but if you DO so, disconnect the RED/GRN wire at the ignition coil+ to avoid damaging the ignition system. With the key "ON", "backprobe" the BLUE wire in the steering column harness connector. You should have power. Depending on the resistance in your test light or the type of flasher being used the power could be constant, or it could flash, like a turn signal. If you don't have power there then, again, you have a wiring issue between the steering column harness connector and the flasher, provided you had power to the flasher in the earlier test.

Okay. Assuming you had power in all these previous tests, now "backprobe" the GRN/ONG and ONG/BLU wires in the steering column harness connector with the stop light switch either jumpered or connected and the brake pedal depressed. If you have power there, but no brake lights, you have a problem in the wiring, sockets or bulbs between the steering column harness connector and the rear of the car. If you don't have any power there you have a problem with the turn signal switch or the wiring up the steering column.

Same thing with the turn signals....with the key in "ACCY" or "ON" as above, "backprobing" the GRN/ONG and ONG/BLU wires in the steering column harness connector while selecting the left and right turn signals you should have power, either solid or flashing, depending on the state of resistance in the circuit. If you have power then the problem is between the steering column harness connector and the rear of the car. If you don't have power the problem is with the turn signal switch or the wiring up the steering column.

Lastly, the dash lights. First, pull the headlamp switch out to the first notch. Rotate the knob all the way in both directions and observe the gauge lights. If you don't have any lights by turning the knob inspect the 2-1/2 amp fuse (the little one in the fuse box) using your test light by probing EACH end of the fuse. With the light switch pulled out one (or two) notches, BOTH ends of the fuse should have power. Again, rotate the headlamp switch knob in both directions to see if you get power. If only one end has power the fuse is no good. If both ends have power and you still have no dash lights you have a wiring problem to the lamps, the bulbs are all blown or the instrument cluster is not properly grounded. There is a ground wire from the cluster to the metal dash frame. If you don't have power to EITHER side of the fuse then you have a problem in the wiring between the fuse box and the headlamp switch.

Hope this helps!
752878
 

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@Woodchuck ; - Applause,Applause!so great a rundown on lighting routing- that even a child could understand it. Thanks!
 

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Also make sure your tail lights and turn signals are using the right dual filament 1157 light bulbs. There are some single filament bulbs that can fit in the socket but they won't work right.
 

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Discussion Starter #13
Okay....

Power for the brake lights comes from the headlamp switch (believe it or not) then proceeds to the stop lamp switch on the brake pedal, then up the steering column to the turn signal switch, back down the column and out through the left kick panel, through a channel under the driver's door sill plate and up the left side of the car into the trunk.

Power for the turn signals comes by way of the ignition switch to the turn signal flasher then up the steering column to the turn signal switch. When leaving the turn signal switch it uses the same "output" as the brake lights as they use the same filament in the rear bulbs for both brake lights and turn signals (the turn signal switch actually "interrupts" the brake lights when the switch is selected for a particular side).

Typically, when you have NEITHER stop lights NOR turn signals the problem can be traced back to the turn signal switch, the wires leading from it back to the rear of the car, the lamp sockets or bulbs, or grounds.

The first place to check is for power at the stop light switch. Disconnect the plug and using a test light probe the pins in the plug. One should have 12V. The other should have nothing. If you don't have any power at either pin you need to trace the wire back to the headlight switch but I doubt you'll find that to be the issue.

The next place to check is for power at the turn signal flasher. Disconnect the plug and check the pins of the plug for power. Again, one should have 12V and the other nothing. If you don't have power at either pin you need to trace the wire back to the splice with the ignition switch "A" circuit. Again, I don't suspect the problem to be there, either.

Next, examine the connector for the steering column harness to make sure it's secure. You can use a small cotter pin or unbent paper clip and your test light to "backprobe", that is to slip the "tool" into the connector from the side where the wires enter the plug so you can check for power while leaving the connector sides plugged into each other. The brake lights should be the solid GREEN wire in the connector. The turn signals should be the solid BLUE wire. The GREEN wire should have power whenever you depress the brake pedal. To isolate the switch, use another small cotter pin, etc., as a jumper to connect the pins in the stop light switch plug. This should provide constant power to the GREEN wire regardless of whether the pedal is depressed or not. If you had power at the stop light switch in the initial test, have jumpered the stop light switch plug, and DON'T have power to the GREEN wire at the steering column harness connector then you have a wiring issue between the stop light switch and the steering column harness connector.

Now, turn the ignition switch to the "ACCY" position. You can also use the "ON" position, but if you DO so, disconnect the RED/GRN wire at the ignition coil+ to avoid damaging the ignition system. With the key "ON", "backprobe" the BLUE wire in the steering column harness connector. You should have power. Depending on the resistance in your test light or the type of flasher being used the power could be constant, or it could flash, like a turn signal. If you don't have power there then, again, you have a wiring issue between the steering column harness connector and the flasher, provided you had power to the flasher in the earlier test.

Okay. Assuming you had power in all these previous tests, now "backprobe" the GRN/ONG and ONG/BLU wires in the steering column harness connector with the stop light switch either jumpered or connected and the brake pedal depressed. If you have power there, but no brake lights, you have a problem in the wiring, sockets or bulbs between the steering column harness connector and the rear of the car. If you don't have any power there you have a problem with the turn signal switch or the wiring up the steering column.

Same thing with the turn signals....with the key in "ACCY" or "ON" as above, "backprobing" the GRN/ONG and ONG/BLU wires in the steering column harness connector while selecting the left and right turn signals you should have power, either solid or flashing, depending on the state of resistance in the circuit. If you have power then the problem is between the steering column harness connector and the rear of the car. If you don't have power the problem is with the turn signal switch or the wiring up the steering column.

Lastly, the dash lights. First, pull the headlamp switch out to the first notch. Rotate the knob all the way in both directions and observe the gauge lights. If you don't have any lights by turning the knob inspect the 2-1/2 amp fuse (the little one in the fuse box) using your test light by probing EACH end of the fuse. With the light switch pulled out one (or two) notches, BOTH ends of the fuse should have power. Again, rotate the headlamp switch knob in both directions to see if you get power. If only one end has power the fuse is no good. If both ends have power and you still have no dash lights you have a wiring problem to the lamps, the bulbs are all blown or the instrument cluster is not properly grounded. There is a ground wire from the cluster to the metal dash frame. If you don't have power to EITHER side of the fuse then you have a problem in the wiring between the fuse box and the headlamp switch.

Hope this helps! View attachment 752878
I narrowed it down to my turn signal flasher. I replaced it and the signals worked for about 30 seconds. They now do not work. So it would seem the flasher is shorting out is my guess. Does this sound possible?
 

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I narrowed it down to my turn signal flasher. I replaced it and the signals worked for about 30 seconds. They now do not work. So it would seem the flasher is shorting out is my guess. Does this sound possible?
a) Did they flash at "normal" speed?
b) When they "stopped working" did the indicator lamp(s) come on and stay on without flashing or did the indicator lamp fail to come on, at all?
 

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Discussion Starter #15
a) Did they flash at "normal" speed?
b) When they "stopped working" did the indicator lamp(s) come on and stay on without flashing or did the indicator lamp fail to come on, at all?
I have the gauges out of the car so I can’t tell what exactly was happening. But it had the click sound and were operating at normal speed. I went out back saw they were working, then tried the right turn signal and got nothing and seemed dead from there on.
 

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I have the gauges out of the car so I can’t tell what exactly was happening. But it had the click sound and were operating at normal speed. I went out back saw they were working, then tried the right turn signal and got nothing and seemed dead from there on.
So switching sides seemed to affect it? Sounds like you've got a bad turn signal switch.
 

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Discussion Starter #17
So switching sides seemed to affect it? Sounds like you've got a bad turn signal switch.
I just recently got around to replacing the turn signal switch and things are going well-ish so far. I now have both brake lights working when pedal is depressed. When pedal is depressed and I go to turn the turn signals on, instead of it flashing, it goes out. Same thing happening on both sides, when the brake pedal is depressed and turn signals are put on, instead of flashing the light goes out. I know lights are getting power and bulbs and sockets should be in working order, because I am getting brake/running lights just fine. When brake pedal isn't depressed I get nothing happening with the turn signals at all. The interior lights in the car are not currently working either (lots of electrical gremlins in this car) so I can not tell if the green indicator light comes on or not.
 
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