Funky lights!!!

[triracer67]

1967, very stock, it has been sitting for a few decades, original fuse box and wiring. Pulled the lights on, nothing. I ran it through the push/pull/swivel cycle a lot and eventually got all lights to come on, kind of a bronco miracle. So, tried same with brakes, blinkers, and flashers. I did replace flashers switch. I have power to flasher and brake switch. No blinkers, flashers, or brakes. Bulbs are good. With flasher switch pulled, I hit brakes and front parking lights get bright, if I turn the blinker left and right, I get the corresponding brake light.

Few questions, should front parking lights be on when all lights are on, when switch is all the way pulled. Did 67 have separate back up lights, what triggers that?

I’m digging in on this one…

 

[Oldtimer]

Back-up lamps are controlled by a switch on steering column, in engine compartment.
When column shift is put in reverse, lever on column activates switch. (assuming manual trans)

Front parking lights are only on at first pull of headlight switch.
When headlight switch pulled all the way out, front parking lamps go out.

You have power in at brake switch. Do you get power out, when pedal is pushed?
Do you hear the flasher switche click when you turn on emergency flashers?

Brake and emergency flasher signals (power) all go thru turnsignal switch.
You may have to pull steering wheel and look at the contacts on turnsignal switch.

Also, if not already done, pull the fuses, and clean them and the contacts in fuse box. They are noted for getting corroded and not working.

 

[Oldtimer]

 

[triracer67]

View attachment 933940

What is best way to clean the fuse contacts in the fuse box? I also looked through schematic and saw brakes went through emergency flasher, I’m going to pull one from old dash and see what happens.

 

[Broncobowsher]

Hazard switch on, hit the brakes. Yes, normal for the front turn signals to light up and stay on with the brake down.
The hazard switch combines left, right, and brake all together when turned on and sends a flash signal through all 3 circuits. Even if the flasher is missing, the switch still combines all three circuits. When you hit the brakes, it energizes everything. The good thing is you have proofed out the wiring and the bulbs.

The front park lights do turn off on the early models. Up to '69. I think it was in '70 they started staying on. May be off a year.
Go back in history a bit. Generators were the common charging system up to the mid 60's. First year Mustangs were generators. Alternators that made good power were a new thing. Also why stuff generally had an amp meter on it up until this time. Charging systems with generators generally sucked. You had to pay attention as battery charging wasn't a sure thing. In order to save every possible watt of power the front park light shut off when the headlights were on. Those were extra lights that generally couldn't be seen with the headlights on. So turn them off and just maybe the generator will keep up with the lights. With the change over to alternators in the mid 60's this wasn't an issue any more. But the legacy continued for several more year. It worked, why change. Well FMVSS standards changed, which made them move that one wire.

 

[Oldtimer]

What is best way to clean the fuse contacts in the fuse box?

Disconnect battery.
I have used contact cleaner spray, Q-tips, and a small piece of scotch-brite pad to scrub the fuse clips.
Some have used a small brass brush.

 

[Broncobowsher]

Also replace the fuses if you are going that far to cleaning the contacts. I had a fuse fail once. Not overload where the tab melted. But the solder joint where the tab inside seperated from the end cap. And it wasn't a complete seperation. I chased that one for a month when it was my daily driver.

 

[m_m70]

I think it was in '70 they started staying on. May be off a year.

confirming mine in my '70 stay on.

 

[triracer67]

UPDATE! Changed fuses and cleaned fuse box the best I could, everything works minus brake lights. I do have power in the wire leaving the brake switch, it enters the taped bundled. Now I get to search under the bronco, and back end. Heck, I even have license plate light. Thanks for all the advice. Thoughts on where to look underneath? I’m thinking a connection since neither work.

 

[Oldtimer]

Are the rear turn signals working?
The single wire leaving brake switch comes out of the harness at harness connector for turnsignal switch.It feeds into turnsignal switch, and then splits into a wire for left brake/turn lamp and separate wire for right brake/turn lamp.

 

[laserfish]

Clean the grounds at the tail light bucket and all others you can find. Coroded grounds cause a world of problems.

 

[triracer67]

Are the rear turn signals working?
The single wire leaving brake switch comes out of the harness at harness connector for turnsignal switch.It feeds into turnsignal switch, and then splits into a wire for left brake/turn lamp and separate wire for right brake/turn lamp.

Yes, rear flashes, blinkers, and running lights work.

 

[triracer67]

Clean the grounds at the tail light bucket and all others you can find. Coroded grounds cause a world of problems.

While the bronco is pretty rust free, corrosions is another story. I’m cleaning a lot to get ground just to check power…

 

[DirtDonk]

Yes, rear flashes, blinkers, and running lights work.

Then all of your wires from the firewall back to the tail lights, are intact and working correctly.
If you are sure that the blinkers are blinking on the bright filament, the brakes are both working on the bright filament and everything else is working, then you need not look at the rear of the vehicle or along the frame. Everything is working past the turn signal switch.
The fault most likely lies in the turn signal switch. But it could be still be in the wiring at the connectors, or wherever things have been messed with by previous owners.
But the most common culprit would be the turn signal switch itself. All of the “bright” lights in the back go through the turn signal switch.

Regarding the flasher units, there are two. One for the turn signals, and one for the 4-flashers.
I’m not sure all Broncos got four-way emergency flashers from the factory in 67. Maybe it was only 66 that was missing them?
Is your hazard switch in the dash, or under it?

 

[triracer67]

Then all of your wires from the firewall back to the tail lights, are intact and working correctly.
If you are sure that the blinkers are blinking on the bright filament, the brakes are both working on the bright filament and everything else is working, then you need not look at the rear of the vehicle or along the frame. Everything is working past the turn signal switch.
The fault most likely lies in the turn signal switch. But it could be still be in the wiring at the connectors, or wherever things have been messed with by previous owners.
But the most common culprit would be the turn signal switch itself. All of the “bright” lights in the back go through the turn signal switch.

Regarding the flasher units, there are two. One for the turn signals, and one for the 4-flashers.
I’m not sure all Broncos got four-way emergency flashers from the factory in 67. Maybe it was only 66 that was missing them?
Is your hazard switch in the dash, or under it?

My 2-prong flasher was broken, I replaced with 3-prong I had, could that we a problem? Yes, flasher switch is in dash.

 

[Oldtimer]

If all but brake lights are working, then as Paul stated harness should be good from firewall to rear bumper.
As stated, verify the flashers are illuminating bright filaments in rear bulbs. May have to pull rear lenses to be sure.
Turn blinker supplies power via wire #44 (violet) to turn signal switch.
Emergency blinker supplies power via wire #810A (red/black stripe) to turn signal switch.
These are all working so these circuits are good.

Brake switch supplies power via wire #810 (red/black stripe) to turn signal switch.
Brake lights are not working.
I would do a detailed inspection of the relatively short #810 wire between brake switch and the 6 contact turn signal harness connector at steering column.
Make sure both red/black stripe wires are present and connected to same pin.

Here is link to seabiscuit68's schematics: https://seabiscuit68.tripod.com/
Scroll down to find 1966-1967 exterior lights and turn signals

 

[DirtDonk]

My 2-prong flasher was broken, I replaced with 3-prong I had, could that we a problem?

Without knowing what the three prong flasher was for originally, I can’t say if it’s a problem or not.
If he second prone is a simple, secondary output, then it’s probably not an issue.
But since all Bronco flashers, whether hazard, or turn signal, are two prong types, I would still get the correct one and put that in there.

 

[Broncobowsher]

My 2-prong flasher was broken, I replaced with 3-prong I had, could that we a problem? Yes, flasher switch is in dash.

99% that is a problem.

 

[triracer67]

Swapped flasher with new 2-prong, no brake lights. Flasher switch is next!

 

[DirtDonk]

What about the second flasher? Have you tried swapping them yet?