Using rear foglights as brakelights

[Ivan141]

I just finished a simple mod on my rear light clusters that makes the foglights come on along with the brakes. Not very usefull (well...at least people will know for d@mn sure when you're braking) and also not very legal, but the electronics needed for this can be pulled out easily.

Here's what you need:
-1 diode, rated up to about 6 Ampere.
-2 regular car type fuses. 10A and 30A

The normal brakelights are 2 21 Watt bulbs which have a 15A fuse. The foglights are also rated 21 Watts so a quick calculation shows that the maximum current will be about 42W/12V=3,5A. I replaced the STOP fuse (located under the dash on the drivers-side) for double the regular value eg. 30A.

Remove the rear light panel from the housing and unplug the wiring, take it inside where the soldering begins. I bent one leg of the diode so I could jam it alongside the Green/white wire in the back of the white connector. Make sure that the diode is pointing in the right direction, the stripe side of the diode should be facing the foglight wire(red) and the other side should be facing the green/white wire as mentioned above. I positioned the diode right behind the connector, then I soldered the 10A fuse to the second leg of the diode (which I shortened by cutting a cm of the leg. Then I soldered a wire to the 1cm bit of leg I cut off earlier and jammed that next to the red wire on the connector. It should be right next to the green-white one used earlier. Solder the free end of the wire to the free end of the fuse and you're ready to go. Pics of the electronics in the lighting panel coming up soon, pics of the rear while braking coming up tonight after dark.

[EDIT] Made a silly mistake..the 10A fuse should be made smaller, I think 5A would be okay. Forgot the fact that the diode will fail above 6A, so it would be safe to use 5A to prevent the diode from failing.[/EDIT]

[Ivan141]

[Ivan141]

Now everytime I brake everything lights up red..the following picture looks a bit odd because I forgot to turn off the flasher on my camera, causing the reflector to light up on the picture as well.


A funny side-effect is that the foglight switch on the dash lights up everytime I brake...I could solve that problem using an extra diode, but I kinda like the effect.

[Mux213]

Hey Ivan,

Looks funny, not sure about the legal issues. In theory you just have a 3rd brake light which happens to double as a fog light.

I'm gonne see what the possibilities are for adding a real 3rd brake light myself eventually.

[robokill]

best mod ever

hebbe

ivan wanneer hebbie tijd????? vrijdag avond

ik spreek je er nog over

[Jesse P]

Another idea:

Replace the bulbs from the rear foglights for a pair of 5/21W bulbs (you'll have to change the "fitting" as well), and connect them to the normal rear+braking lights. When done, you'll have 4 normal rear lights, which become brighter while braking!

[Mux213]

Jesse, but then you have the problem that you no longer have a fog light, which is manditory in NL.

[Ivan141]

Actually not a bad idea..you can still use the 21Watt wire going through the brakelightbulb used instead of the single coil 21Watt bulb that usually works as the foglight. I'm not looking forward to replacing the fitting though..it's molded into the plastic and I dont want to ruin my only rear light modules. BTW, I found a stupid little mistake in my component choice. The 10A fuse should be replaced with a 5A fuse since the diode is only capable running 6A.

[KristianAE86]

I got that too.. really much nicer than stock twin lights.

Also i will all the 4 light com on when clicking the lights on - not just for brake lights