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Interiors, Dash, Lights and Electrical Everything Inside

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  #1  
Old July 15th, 2017, 08:05 PM
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Default Tail Light gremlin

I hope i explain this correctly and also hope other can direct me to the possible fix?

When I pull the headlight switch out to the first position the hood running light and tail lights come on. When I press the brake pedal the passenger side brightens but NOT the drivers side.

BUT when I pull the switch to out fully to turn on the head lights, the tail light out out?

Any pointers?
21 circuit from E-Z wiring is what is installed

Thanks
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  #2  
Old July 15th, 2017, 09:18 PM
AZKen AZKen is offline
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Default Re: Tail Light gremlin

You would first want to switch rear bulbs and see if the problem follows the bulb. Also, on the one that won't light, stick a temporary ground from bulb socket to a good ground at rear while applying brakes. Report what happens.

Then: All I can say is re check the circuits once you know how it's supposed to be wired. The stop switch has a hot-all-the-time wire on one terminal and a wire that goes to the turn signal switch from the other terminal. Then two other wires come out of the turn signal switch. One for left brake/turn and one for right brake.turn. If you check at various connections/connectors/terminal blocks with a 12V ice pick tester light. that way you can see if 12V is present all the way back to tail light. (of course, be sure brake pedal is applied during all this). Take out the bulbs and touch the proper contact inside the socket with the probe and attach it's wire lead to a good ground back there. See if you can get both left and right to light the test light with brake applied. If that works, then it's the bulb or the socket is not grounding. If one does not light still, follow the wire for that bulb back until you find power. Report what happens.

I would like to know if the rear turn signals work?
You have a dual filament bulb back there. The rear running light "filaments" are wired to the headlight switch. The turn/brake filaments are wired to the turn signal. Don't get that mixed up. Follow the 1960 Diagram, the EZ wire instructions are generic. Don't let colors fool you, be sure the hook up is correct functionally.

Could be a simple ground problem or bad bulb.
Could be headlight sw not wired correctly, turn signal sw not wired correctly, or other wiring. The tests and wire checks above will start to tell.

Last edited by AZKen; July 15th, 2017 at 11:23 PM.
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Old July 16th, 2017, 12:38 PM
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Default Re: Tail Light gremlin

Quote:
Originally Posted by jbgroby View Post
BUT when I pull the switch to out fully to turn on the head lights, the tail light out?
For this to happen I would suspect the headlight switch. Are you stepping on the brake when you turn on the headlight? Did the brake lights work when the headlight switch all of the way in?
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Old July 17th, 2017, 07:14 PM
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Default Re: Tail Light gremlin

sounds like you are losing ground to rear light. sockets go bad.ground is back feeding. my 66 did the same thing, i was able to temporarly get connection, by cleaning and wiggling bulb. did this numerous times. got tired of people telling my brake light wasn't working on one side. i installed led replacements. they come as a whole light. you will need to cut the socket off of the new light, they are made to go in place of the bulb, but that will not fix your problem, if you don't eliminate the bulb socket. i ordered them from cpp or tuckers, can't remember. have had no problems since
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Old August 31st, 2017, 02:35 PM
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Default Re: Tail Light gremlin

Update, I got it fixed, I did not realize I had the tail light wire on the wrong post in the HL switch. I now have running tail lights with headlights on, so I can safetly drive at night. BUT, I have no break light when I hit the pedal on the drivers side yet. Still working on this.

Also the harness comes with a 30 amp relay for the head lights, but when I turn on the high beams, after about 5-7 seconds all the headlight go out. I turn the lights off and then they come back on. The dash lights and spotlight never have any problems. I'm going to try to see of the high beam floor switch is the issue (new and came with wiring kit).
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Old September 1st, 2017, 01:59 AM
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Default Re: Tail Light gremlin

Did the wiring kit come with a wiring diagram? If it did, would you be able to post it here? The wiring kit make it difficult to troubleshot not knowing how it was assembled, might not be the same as the original harness (you did mention a headlight relay).
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Old September 3rd, 2017, 05:38 PM
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Default Re: Tail Light gremlin

OK, will scan it Tuesday when I get to work and post.
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  #8  
Old September 6th, 2017, 12:43 AM
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Default Re: Tail Light gremlin

Headlight switch has a thermal overload feature. Those contacts are corroded. If it's a new switch, then some Chinese guy screwed up the assembly. The overload metal contacts are cooling off and resetting. You may have a good switch and thermal overload contacts and your problem is that something else is overloading. Bad relay, bad dimmer switch, wiring messed up/small short, bad filament in a headlight, headlight connector.

The brake light issue, on one side, should be easy to trace. It's not beyond the realm of possibilities that the two are related.

Last edited by AZKen; September 6th, 2017 at 12:55 AM.
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Old September 6th, 2017, 02:02 PM
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Default Re: Tail Light gremlin

Thank Ken, I'll check with NAPA to see if there HLS is made in the US, would you happen to have a source you could recommend. The harness came with a 30 amp relay (although when I emailed ez-wiring, they said it did not?) I can see the relay and will take a picture of it to send to them...... The dimmer switch will be the easy to change as well.
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Old September 6th, 2017, 07:31 PM
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Default Re: Tail Light gremlin

Don't forget that you can bypass certain components like the dimmer and just touch/connect the wires together for high beam and test. Everything you buy anywhere, including NAPA is Chinese or Mexico. If the HLS is old, clean the thermal contacts. The best HLS would be a good original donor or NOS. Not too much to go bad on them....or this

There is NO headlight relay on a 1960. The only relay is the horn relay. That is what the supplied relay is for. Do not use a relay in the headlight circuit.

There is one wire from the headlight switch to dimmer input terminal. Then a wire from low beam terminal on dimmer to all low beam contacts on bulb connectors. And a wire from dimmer high beam terminal to all high beam contacts on the bulb connectors.

Each bulb connector has a ground wire to be grounded.

It does not matter which terminal on the dimmer is used for High and which for Low beam, just so the high and low wires connect to bulb connector properly. See manual electrical section/wiring diagram TPM-6750-1.

Last edited by AZKen; September 6th, 2017 at 09:28 PM.
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