Has anybody installed this to ward off tailgaters?

http://www.kahtec.com/smart_stop.htm

Seems easy enough, but have not really looked at the wires to the 3rd brake light. The rubber housing is pretty thick. For those who have installed it, any tips? Does installing it also modulate the brake light in the spoiler?

 

Subscribed! I would like to do this too.

 

Completed this simple little project several weeks ago.... I installed the "intelligent" version - 6 rapid flashes followed by repeating 3 flashes after each steady on while your foot is on the brake pedal.

PorscheCrazy- To answer your question for the 991 without a fixed wing in the rear, you would need 2 of the modules from Kahtec if you want both Upper and "Lower" (on the active wing) brake lights to blink when active. In my case I installed only for the upper third light, since most of the time I am driving with the active wing in the down position. When the wing raises, the upper third brake light is not active. If you have any of the fixed-wing options, you only need one unit and may need to tap into a different location than what I did.

I do have a detailed DIY on this, with pictures including where to tap into the brake light wiring -- just haven't had time to post it up.

Here's a pic of the wiring you will tap into for the Upper third brake light.

 

Jawells - You ARE the mod king!! Knew you would know how to do it! Thanks for the information on the spoiler brake light. I thought that would be the case, but was not sure. Do you know where the wiring is for the spoiler light?

The pic you attached -- not sure what that is. I would have assumed that you could have accessed the wires form the rubber boot from you previous post on taking off the engine cover.



Anyways, thanks for the information. Getting ready to order. Will wait for your post on steps taken. I assume you used splice connectors?

 

PorscheCrazy- the pic I posted below is a location just below the rear window (interior) where the Upper brake light wires exit to the rubber boot that is in the picture above... ;-) Those wires are just right in front of you when you remove the interior trim panel just below the window, and push the insulation material to the side. IMO it was better to tap into the wires on the interior, in a safe, weather-proof location. Plus, you have to place the little black box / module from Kahtec somewhere, and not sure that I'd want to try and place it within the engine cover. You could probably tuck it in somewhere inside the grill cover, but again, not sure and I would be worried about weather exposure.

As for the "lower" or wing-mounted brake light -- the wiring is more difficult to reach, but accessible from the rear, in the engine bay. I'll post a pic later... I didn't put much thought into the ideal location to splice into the wire harness, but shouldn't be too difficult to figure-out.

The Kahtec module comes with some clamp style splice connectors. They do work, but my experience is that you will get a much better connection with little chance of failure if you solder. For disconnecting, just solder male/female bullet connectors to the ends you are joining.

Hope that helps!

 

Thanks Jawells1, I just ordered the Delay model.

 

You da man! Thanks Jawells. Thinking of getting one from Amazon with a smaller footprint that would tuck into the boot or other small crevice and is programmable.

 

Cool. I would be curious what vendor you go with, and how their product works.

As for placement of the black box - if you are doing the aero-wing brake light, I imagine you could stow the box down in the engine bay. With wing up you can see the wire on the left side, come up and attach to the articulated "hinge" that raises / lowers the wing. It is clad in black - I'll assume the wires are same color for +/-. I haven't traced the wiring from the wing, but assume it must run down and come back into the car on the drivers side. I haven't looked over there. For the Upper brake light I don't think you have too many options were to stow the box if not inside the car, without the wiring having to run across under-the-hood exposed surfaces and what-not.

I should have the DIY posted later....

 

Interesting mod. I'm not sure if I'd want my third brake light flashing every single time I apply the brakes for a measurable length of time, though.

I recall many manufacturers introducing flashing third (and main) brake light systems years ago. One of them was BMW; the 3 series had an awesome system that would get brighter as you applied more pressure to the pedal, and it would illuminate a different set of (additional) brake lights that would flash if you applied more than, say, 70% pressure.

 

Yeah, I was concerned with this as well.... Kahtec offers a version of their module that only flashes 6 blinks each time the brake pedal is pressed, so as long as you have your foot on the pedal it remains steady-red. However, I went with their version that blinks rapid 6 times and then only 3 blinks every 6 seconds.

And to be honest, I wanted the blinking pattern for when I am in traffic -- I've watched countless collisions happen in stop-and-bump traffic due to people being lulled into sleep by the constant red lights in front of them... I like the fact that my light will blink enough to get attention before someone bumps me. I am all about "defense by offense" and will do what I can to avoid someone hitting me. This seemed like a cheap, simple way to do so. If I feel someone behind me will be upset or whatever by the blinking, I'll just raise the wing which I didn't modify....

 

Understandable. I don't think it will upset anyone behind you. I just think the constant blinking with *any* brake application would be overkill.

I absolutely agree with your defensive driving position, though. Even if it saves you a single close encounter with an accident, it'll be worth it.

 

Well, I looked to see if I could tap into the 3rd brake light wires via the rubber boot on the left side of the engine cover. Looks like a no - go. I removed the top of the boot and the boot actually extends about another 12 inches or so inside the engine cover. No way to get to the wires that way. I then removed the bottom of the boot, and while you can see the wires, it is hard to access because there is practically no excess to work with. So, it appears the only way to do it is from the inside as Jawells outlined (or will outline). I suppose you could take off the engine cover and work on the wires where it connects to the brake light, but that may be more work.

 

Sorry took me so long, but I finally got a few minutes to post-up the DIY....
Let us know how your project goes!

 

Installed my Kahtec 3rd brake light "Delay" model tonight. Took all of :15 using Jawells DYI instructions. Didn't even read the instructions from Kahtec and it worked perfectly the first time. Thank you again Jawells!

 

I have had a blinking 3rd brake light in my last two cars and want to add one to my current 997 4S coupe (I know I am in the 991 forum BTW). I found the Kahtec flasher last week and contacted them to see if their unit was adjustable as I thought that 6 flashes was overkill. I have been behind cars that apparently have their unit and it is annoying as heck because all it does it flash constantly when in traffic. I was hoping for one like my last that flashed 4 times and then sensed when you were in stop and go traffic and did not constantly flash unless you were off the brake for 40 seconds. I have tried to find this older unit and so far no luck. Chaotic replied to my question that their unit is not adjustable to modify the flashes unfortunately.