Turn Signals Not Working.....

[clintonvillian]

Every light works properly, EXCEPT the rear turn signals will not flash when the lights are on. They just stay lit up solid red.

When the lights are off they work fine, any suggestions?

 

[DirtDonk]

Hmm, well that sure has the earmarks of a bad ground. Is there any new paint or excessive rust on the body where are the tail light housings bolt on?
When you pull the bulbs out and look in the sockets, are they clean and straight?

 

[Okie69]

I had a similar issue recently. I ended up chasing grounds and then replacing the headlight switch and that fixed it.

https://classicbroncos.com/forums/threads/brake-light-running-light-issue.314620/

I would definitely look at grounds real close like Paul suggested. Maybe even add a couple just for fun.

 

[clintonvillian]

Okay let me ask you this...

If your hazards are on, and you hit the brakes, do all four hazards stay on solid until you release the pedal?

 

[Speedrdr]

From my experience in a classic Bronco (previous ‘77) the flashers only worked (flashed on/off) As long as you don’t press the brake pedal. Do not know how or why this occurs.

Randy

 

[Broncobowsher]

Okay let me ask you this...

If your hazards are on, and you hit the brakes, do all four hazards stay on solid until you release the pedal?

That is correct.

 

[Broncobowsher]

From my experience in a classic Bronco (previous ‘77) the flashers only worked (flashed on/off) As long as you don’t press the brake pedal. Do not know how or why this occurs.

Randy

This happens because the brake lights are energizing the brake/turn circuit. Hazards don't turn on the turn signals. The merge both front turn signals and the brake lights into a single circuit and put flashing power to it. Stepping on the brakes while the hazards are on bypasses the flasher and powers up the whole batch of combined (combined from the hazard switch being on) lights with steady on power from the brake light switch.

You could remove the hazard flasher, pull the hazard switch on, and all the lights will come on with the brake lights. You would also get all 4 lights flashing from the front turn signal backfeeding the whole combined mix of lights.

 

[clintonvillian]

Okay thanks guys.

I figured out the problem. The LED bulbs I installed apparently do not need the resistors. Once I took the resistors out everything works fine.

 

[DirtDonk]

In older vehicles only those that had separate rear flashers/turn signals from the brake light such as those with amber colored turn signals could keep flashing when the brakes were applied.
As Bowsher said, if the turn signals, hazards and brakes all share the same circuit, then the brake overrules the hazards

 

[DirtDonk]

Great news. Good catch on your part.
I’ve always heard that LEDs were finicky if you put them in the wrong way, but I think that’s the first time I’ve heard someone having to remove the resistor.