My last electrical gremlin? One brake light...

I think all electrical items on my car are working after putting it back together. Except for the passenger brakelight. The passenger tail light works ok (dim though) and the passenger flasher works ok with emergency flashers on. But no brake light. (I haven't checked the regular turn signal on that side but thought it would work since the emergency flashers do.)

All wiring, bulbs, etc are new but I've learned that doesn't matter (installed 2 defective, mis-wired parking lights on front). Any idea to narrow my uninstall-and-replace search, which is kinda expensive? Thanks!
 
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If the flasher works, then the wiring to the back is ok.

I didn't have 4 way flashers on my '65. Not sure how the '66 has the switch intergrated into the wiring. Is is built into the column, or is it a separate switch?

The rear signals get the power individually from contacts in the sgnal lamp switch. If the voltage is good coming out of the column connector, then I would look at the flasher wiring/switch.
 
If the flasher works, then the wiring to the back is ok.

I didn't have 4 way flashers on my '65. Not sure how the '66 has the switch intergrated into the wiring. Is is built into the column, or is it a separate switch?

The rear signals get the power individually from contacts in the sgnal lamp switch. If the voltage is good coming out of the column connector, then I would look at the flasher wiring/switch.

The emergency signal switch is in the glovebox, looks like it was installed at the dealer back in the 60s. The turn signals should work, it's the passenger brake light that's not working. The green/blue wire carries the turn signal and the brake light to the passenger rear I think. The problem must be under the dash from the brake switch to the green/blue wire, I'm guessing... Is this possible?
 
Could be a bad bulb. Double check the bulb and test for current at the bulb socket. If you got nothing there then work backwards.

You can also go the other way and work forwards but I don't like going that route myself unless I suspect the problem to be closer to the start of the circuit.
 
from looking at the diagrams, you've got your turn signal power coming from the back of the ignition switch into the flasher, then into the column connector on a blue wire, your brake signal is coming from the brake switch on a green wire. the wire coming out of the turn signal switch to the column connector and back to the pass. tail light should be orange and blue. the brake and turn signal signal are both sent on that wire. i'd check the connection at the column connector, maybe that is loose or something. if one of your brake lights are working then power from your brake switch is good. you're probably looking at a bad turn signal switch.
 
The green/blue wire carries the turn signal and the brake light to the passenger rear I think. The problem must be under the dash from the brake switch to the green/blue wire, I'm guessing... Is this possible?

No, If one brake light works, it’s not the brake switch.
The schematics I have show an Orange/Blue wire, but regardless, if both flashers/signals work, it’s not the wire or the socket or bulb.

First check all signals and then the 4-way flashers and report back.

Have someone watch the lamp (or set up a mirror) so you can see the bad brake light. Hold the brake pedal and slowly move the signal lever up and down to see if the light comes on.

It appears something may have happened to your new signal switch, or perhaps a couple wires are swapped at the plug.
 
Fixed... maybe

I found that the passenger rear brakelight and turn signal did not work. But the turn signal indicator in the dash flashed normally and the running light at the passenger rear did work.

So I was fiddling under the dash and tightened the connector of this orange Y-connector where it leads to the tail light harness (although the connector seemed already tight). And now I have lights on the passenger rear. The connections at all the bullet connectors are crummy even though everything is new, meaning a slight twist here or there and various lights go out.

Can I use dielectric grease to make the connections better at all the bullet connectors? Will the grease transfer electricity or just keep moisture out?

Also, the passenger rear light is dim, in all it's functions. I replaced the tail light bucket, bulb, and all wiring as I said earlier... Also, the ground seems ok. (The backup light below the bumper works fine off the same ground.) Could this be caused from a poor positive (+) connection?

Thanks for all help!
 
I found that the passenger rear brakelight and turn signal did not work. But the turn signal indicator in the dash flashed normally and the running light at the passenger rear did work.

So I was fiddling under the dash and tightened the connector of this orange Y-connector where it leads to the tail light harness (although the connector seemed already tight). And now I have lights on the passenger rear. The connections at all the bullet connectors are crummy even though everything is new, meaning a slight twist here or there and various lights go out.

Can I use dielectric grease to make the connections better at all the bullet connectors? Will the grease transfer electricity or just keep moisture out?

Also, the passenger rear light is dim, in all it's functions. I replaced the tail light bucket, bulb, and all wiring as I said earlier... Also, the ground seems ok. (The backup light below the bumper works fine off the same ground.) Could this be caused from a poor positive (+) connection?

Thanks for all help!

My lights were out recently....turned out the plug worked loose on the brake light switch. Also, if I remember right dielectric means an insulator. Maybe try sandpaper first?
 
My lights were out recently....turned out the plug worked loose on the brake light switch. Also, if I remember right dielectric means an insulator. Maybe try sandpaper first?

Thanks i think i will try unplugging everything, lightly sanding the connections and plugging back in. I've been looking around online and that's right, dielectric does not conduct electricity. Apparently there's something called conductive grease for that. I had never heard of that before.
 
Fixed, Thanks

This is one of a few posts that have been solved since I first posted in '08. Rusty67 gets the prize for this one. :) It was a bad bulb. The second bad LED in a row on that side apparently. So I used a standard 1157 and everything worked again... Thanks all!