Rain lights


For the Sep event at Roebling, you need to have a FIA approved rain light on the back of your car in order to participate in a “Rain Race”. The light needs to be located in ~ the central 1/3rd of the rear of your car, not towards an outer corner. The light needs to be steady on. There’s useful info in both the MidAtl category and also the Electrical category.

On 1Jan19 your steady-on rainlight needs to be able to blink upon application of the brakes. Most rain lights come with 2 wires so it’s just a matter of wiring the blinky wire to your brake lights.

This is all covered in the SE Supps. SE Supplemental Regulations - Google Docs


Man, it would be awesome if the Southeast region and Mid-Atlantic region could get on the same page with a single set of requirements. As it stands, they are in direct conflict with one another. Given the amount of crossover between the two regions, this isn’t good.




Thinking more about this. I don’t know about other FIA lights, but here’s how the “Afterburner” light works. It has two circuits. One for blinking, and one for steady-on. Here’s the thing though - the steady-on circuit overrides the other one.

So, if you wired the light to be blinky all the time, but hooked it up so that it went solid when the brakes were applied, that would work. I’m not sure how one would wire it up to work the other way around, though, since when both circuits are active, it defaults to steady-on.

Maybe other lights (like say the Lifeline) work differently?


No worries. Burueacracies move slow. Here’s what I think is going on.

MidAtl was point man in this. SE tried to align their rule with MidAtl, but that ran into difficulty so the two did not end up precisely aligned.

Then, I think, NASA HQ got involved and told the regions that they want blinking on braking behavior for these rainlights. Hence the guidance in the SE Supps. MidAtl prob just haven’t made the change in their Supps, or maybe they’ll deal with the change informally, I dunno.

The NASA CCR has small changes pretty routinely. They’re just not announced. I don’t know precisely what NASA HQ told the regionals, but it involved blinking on braking. Prob see it in the CCR soon.


My car’s not at home right now, so can’t check. Seems like awful strange behavior to engineer into the device. Could definitely put a monkey wrench into NASAs scheme.


It can’t both blink and be steady-on at the same time. If both circuits are active, it has to default to one or the other. For the Afterburner, the circuits are labeled “rain” and “brake”. The “rain” circuit is blinky, the “brake” circuit is steady-on. Pretty much the opposite of the forthcoming NASA requirement.

AfterburnerRainLight.pdf (323.7 KB)


I’m missing something. I can’t tell how much of what you are saying is from your own experimenting with the Afterburner, or from the manual.

I have the afterburner installed, but I don’t remember which wire I connected to the switch.


I’ve been using the Afterburner since MA mandated rain lights last year, and have rewired it a few different ways as their rule became more prescriptive. I posted the manual just as a supplementary reference. I realize the manual itself doesn’t go into detail about this, but I guarantee you that this is the way that it works:


There would be no way to wire it up so that it functions the way the SE supplemental rule and presumably the forthcoming NASA national rule requires. (Solid-on during a rain race, and blinky under braking.)

Now, I only have experience with the Afterburner. That one was explicitly mentioned in the MA supps, so it was the easy-button for compliance and quite a few of us bought it. Other FIA rain lights may function differently.


Ok, I’ll get the word out to the brass. It’s important for them to know that their idea won’t be as easily implemented as they envisioned. You’ve done them a service.


I’m going to go ahead and order one of the Lifeline rain lights, since I’ll need one for the new car eventually anyway. I’ll report back as to whether or not it functions differently.


I purchased the afterburner a few months back. After cmp in may (i think). Julian is correct. The afterburner cannot be wired the way they are proposing. Steady on i believe overrides all. Blinking will not work when brakes are applied. I havent tried to wire it the other way so steady on works when brakes applied.

Ill be honest, and im sure i speak for a few when i say, spending time on something that should have been figured out far before implemented is just wasting our time.


Yes, in a perfect world it would have all been figured out correctly the first time. MidAtl tried to be the pointman and do something that would help people. SE tried to follow along 1) SE liked the idea and 2) Compatibility between rules. But not every good idea works perfectly the first time. Then (this is conjecture) the regions got guidance from National HQ on rain lights.

It took a couple hours for me to install the brake light, find the right wire to splice into, and put a switch on the dash. So I’m now legal for rain in SE and MidAtl. If there is a change for 2019 where they, prob National, wants the opposite behavior, it will only take a moment to make the change.

Since the blinking behavior, identified now as likely erroneous, was oriented on next year, who’s going to waste time on making anything blink?