Hot Rods No stop or directional lights...

I have a Fiberglass 41' Willys I bought a few months ago, it was a project car with the body sitting on an S-10 chassis (Looks like the previous owner used most of the Blazer harness). Most of the wiring seems fine.

Here's the problem...
My Brake, Tail and Directional lamps all work... EXCEPT when I turn on the headlamps! Directional lamps won't blink (Or brighten) and my Stop lights don't work.
The only rear lamps "Working" are my tail-lamps.
I have 10 gauge Ground wires on both tail-lamps (Going to the chassis),
I checked all the feed wires (& connections) to both tail/directional lamps &
All the fuses are in good shape.
I didn't checkout (yet) the wiring on the aftermarket headlight switch, maybe a wrong switch or bad ground?
>> I'm thinking, if all my lights are working when the headlamps are NOT on, then it has to be a ground wire needed somewhere!
Has anyone experience a similar problem?

 

My first thought is the headlight switch/wiring. May not be it, but if I were in your place that is where I would start. Only because turning on the lights has the effect you described. In general, they are two different circuits. The 'park' lights, front and rear, run through the h/light switch. The brake/turn lamps (filaments) are supplied through the brake light switch and routed through the turn signal switch.

Ray

 

I had the same problem with my '50 pickup and the Trailblazer harness. When I switched to aftermarket tail lights I had to change the Stop Light Switch under the dash, even though they weren't LEDs.
Part # 15128874
Stupid little $10. part cured the problem instantly!

 

Just noticed you're from Ormond Beach!
I've got a home down there, beachside.
I'll look for your Ride next time I'm down.

 

LM487 Flasher may be need also. Around $35.00.
That's more for inadequate wattage. Usually evidenced by slow or rapid flashing.

 

fiberglass? check your grounds.

 

I recently had an issue with one of the taillights on my beater truck. The taillights worked good alone, the brake and turn lights worked good, alone, but turn on the tail lights with the turn and only the tail lights would light up. Grounding the bulb housing fixed the issue. Turned out the bulb socket has some corrosion on the inside of the housing where the bulb made contact with the housing that couldn't be seen until the bulb was removed. After I replaced the housing, everything works. You have a ground issue. Gene

 

I'd pretty much agree with what 50Dodge4x4 said. The problem may be inside the sockets.
On thing? You do have dual element bulbs in the lights and dual element sockets. It sounds crazy but I've run into at least one rig that someone wired both the stop/turn and tail light wires to single element lights. The stop or turn would work as long as the tail lights weren't on but wouldn't work when they were on. That one had some after market single element lights on it.

 

My guess, too.

Ben

 

Thinking on it a bit. Have you got a good ground lead going from the chassis to the battery?
If the ground from the battery just goes to the block you may not have a good ground connection between the frame and the block because of the engine mounts isolating the block and trans from the frame.

 

Bad turn signal switch in the column.

 

I'll go with poor or no grounds to the headlights....

 

Front Parking Lights on my Fairlane were not self-grounding because we powder coated the front bumper several times. I ran a wire from the back of the fixture to the frame, and that did the trick!
-- They affected my dash lights, brake lights, turn signals worked in back, but not front, and flashed on the dash!

 

I'm from R.I. & moved to Fl. 6 years ago... (I'm near Nova Rd. off Grenada)

 

More and better grounding helps. I don't like the idea of using a salvaged harness and an aftermarket HL switch, possible compatibility/ wiring issues.

 

Yes, I have...
Good ground from Frame to Battery
Good Ground from frame to Engine
New 51' Pontiac Tail-lights (Grounded to Frame)
New 1157 bulbs..

 

The only electrical connection between the headlights and the turn/brake lights should be through the grounding if the car is wired correctly, and there's no reason to think it's not as they work when the headlights aren't on. The brake/turns power should NOT be connected to the headlight switch in any way. Try running chassis grounds to each headlight, that should clear it up.

 

I have owned a dozen or so chevy "plastic fantastic" in my life. Nearly every electrical demon I ever chased was solved by a ground strap. By ground strap I refer to both a section of auxiliary wire added to assure good clean and consistent ground and a drink I named in honor of the lost hours spent re-wiring my cars.

"The Ground Strap"; Pour 2 fingers (I use my index finger and my pinkie as a standard measure) of Kentucky Bourbon (Makers Mark is not made in Bowling Green but I prefer it persoanlly) over 4 medium clear ice cubes and serve in a chilled copper Moscow mule mug. Aluminum mug would also work but copper is more traditional.

Test your pour with an ohm meter, it should read 0.3 Ω

In one respect or the other, I think a ground strap would help.

 

My ground straps are generally the braided type;

Personal 'Ground Strap' is three fingers of George Dickel, the purest Tennessee sippin' Sour Mash in these continental United States.
Preferred by long haul truckers coast to coast.
It was circuits looking for grounds in a '57 White Freightliner that drove me to George Dickel... and I never had the opportunity to thank him!

 

I have never tried it Mike, I will make it a point to do so at my earliest convenience...which is right about now.

 

I knew there was another reason I liked you Billy?
I do some of my best troubleshooting with a couple Makers in me first.
And a fire extinguisher closeby when wireshooting.

 

GM tilt column? With a 4 way flasher "push button"? I had all kinds of light problems, and went crazy trying to figure out what I did wrong. 4 way flasher button was partially pushed in and had everything messed up.
And I run grounds to EVERYTHING in the lighting system; P.I.T.A. tracking down those electrons sometimes!

 

Try running a ground wire directly to the bulb housing....temporary test. I've had metal sockets not grounding the bulb properly.
Clark

 

Your add said it is a FIBERGLASS body,,,,,,,,,fiberglass has no grounding aspects that you would need to make lights work,,,,,so they feedback through the elements in the bulbs,,,,,CURE is ground wire from the light sockets to the frame for all the lights,,,,,then things will work properly.....Good Luck

 

.... But the OP makes no mention of grounding for the headlights, which is very probably the problem.

 

It's not noon here yet so no drinking jokes...yet. On the serious side sir, grounds can be a tricky item. They can "chase" other routes to get to ground like lightening will find the nearest available path. The fact that your lights work until the headlight switch is pulled may be telling you that the headlights are striping the ground path from the other lights.

I had a 68 vette (OT but it is relevant), 68's are the only C3 vettes that came from the factory with four taillights (two brake and turn signals on each side and reverse lights below the bumper, all the other round light cars had one brake light next to a reflector/reverse light). That rule does not apply to the "dead man's curve option". If you disconnect the ground on the inside light the turn signals will blink in sequence rather than together as the light that is on when blinking will seek the ground from the other lamp turning it off temporarily, then the process reverses.

I'm not saying this is your issue but a possible answer or a clue. It is hard to find this error since each light does have a ground wire attached but somewhere one of them is not making proper ground so visual observation will have you chasing a herring.

I normally trouble shoot wiring issues by going back to the last item installed on the car, disconnect it and work backwards. In this case the answer lies in your sentence from your post "My Brake, Tail and Directional lamps all work... EXCEPT when I turn on the headlamps!" The switch might be faulty, you can wire around it temporarily to test that assumption easy enough. If you can unplug the rear harness, do it and see if the reaming dash lights and front markers if so equipped are working with the headlights on. Its a puzzle, not a conundrum, and puzzles can be solved with patience and logic. Heavy on the logic.

If you weren't physically as far away from me as humanly possible while still being in the same county I would come help sort it out.

Enough words, almost noon. Now where did I put that copper mug?

 

After a short recess (Bike Week & Turkey Run) I decided to work on the Willys again.
I read all the replies:
Let me say that there are ground wires on every lamp...And I double checked for good grounding!
One thing I didn't mention is that when I apply my brakes (Running or not) my dash lights go on and then go off, when I take my foot off the brakes, as if they were attached in one circuit!
Also, when I turn my emergency flashers on with or without the car turned on (Or the headlights on) I just have tail & parking lights, like I did before, as if I had my headlights on.
I should have never gave up drinking or womanizing...
Because I never had any of these problems, until I quit!

 

A bad bulb itself can drive you to drink. I would look at the parking and taillight bulbs as a start.

 

Two things to check when you turn on the lights are both elements in the bulb lit? Check to see If someone put a single contact bulb in a double contact socket. The single contact bulb will bridge both contacts.