Brake lights flashing in extreme cold

Well, the parking brake explanation does not appear to check out. At least release the parking brake and leaving it off after flashing is noticed does not appear to make any difference.

It appears swapping in the stock bulbs corrected it. Cannot say definitively as the temp is boarder line and warming up. They were only flashing every 5 to 10 minutes before the switch and it warmed about 3 degrees during that time.

I'll leave the stock bulbs in and tentatively say it was the LEDs. If I see flashing again I'll update.

To anyone removing taillights in the cold, the housings get brital. The two lower plastic tabs that hold the metal clip for for the retaining screw both shattered and allowed the clip to free spin.

The actual wiring connectors remain nice and flexible though.

 

Where do you live thats -40? That’s an extreme environment for equipment.

 

You would be surprised at how a loose ground in the system will cock up all the works. The cold could be contracting a ground wire connection somewhere.

 

I live in Anchorage, AK (which generally stays above -20), however the interior gets colder, so when I travel I can see extreme cold.

 

My guess would be the electrolytic capacitors in the LED driver not up to the extreme cold.

 

0.1 millivolts at 0.3 microamps are constantly on the circuit at the contacts for the bulbs.

Given this

I'm inclind to say the low contentious current was charging components in the LEDs, which were then discharging enough power into the entire circuit to also illuminate the stock 3rd break light. The power must be coming from the brake light circuit as removing the relay stopped the cycle.

@Stocklocker thank you for taking the time to write such a detailed reply. I foolishly thought LEDs were simpler than they are.

 

Figured out how to convert the videos to gifs

At about -8 F


At about -30

 

How and what is wired to the camper?

 

Just the break lights via a plug and play harness on the drivers side.

 

You are welcome. Glad you got it figured. Happy new year.

 

Is there a trailer brake controller installed?

 

Yes. Redarc Tow Pro Elite.

 

If the flashing returns, unplug it and see what happens.

 

Well, two cold (-10 F) mornings in a row and no flashing. The only change has been the LED bulbs, so I'm pretty confident in blaming them.

 

This is happening to one of my vanity lights

 

My limited, and probably over simplified, understanding is that some circuits are designed without a true neutral and that this results in a constant small amount of power being on the circuit. This is not enough to turn anything on, but is enough to charge the capacitors in an LED, which if not desinged for it can then discharge that stored power into the circuit.

Of course all that only applies if you have LEDs in the vanity lights.

Most Diode Dynamics LED bulbs are rated to -40, but not the vanity light bulbs. You could call and ask DD about it. You could go back to incandescent. You could redesign the circuit to have a true neutral (beyond my competency level currently).

If it is only one out of 4 vanity lights, I would try switching the bulbs around. See if the flashing moves with the bulb, or not.

Good luck and let us know how it goes as I am interested in knowing if the vanity lights are something I should leave stock.

 

This thread is dead? Not yet, I said.

Myself and a couple people in this thread > Strobing third brake light | Tacoma World have had the same issue. The only thing we all have in common is the Redarc Tow Pro Elite brake controller. I live in New England and any time it gets below 15°, the third brake light starts to blink faintly until it warms up. I do not have LED tail lights, so the tails don't light up at all. It has to be an issue with that particular brake controller, if I unplug it, the blinking goes away immediately. Now, I'm no electrical engineer, but if I were to guess, if the LED bulbs in the third brake light were swapped with non LEDs, the blinking would stop. However, that wouldn't necessarily mean that everything is solved. Why is there any power being supplied to that light at all if the truck is off? With this particular controller we know that there is constant power to the knob in the cab because if you press the button while the truck is off it will glow blue (if orcs are close). So my real question is why the cold?? What does the temperature have to do with anything? I want answers. Anyone have an idea?