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914World.com _ 914World Garage _ Fog light operation
Posted by: boxsterfan Dec 6 2013, 06:24 PM
Are the fog lights supposed to work independent of the headlights?
Mine never come on unless the headlights are on.
Posted by: michael7810 Dec 6 2013, 06:31 PM
Mine come on with the parking lights or low beams.
Posted by: Bob L. Dec 6 2013, 07:17 PM
I don't have them in my car but I have seen "fog light switch"s for sale. I assume they work on their own.
But then:
When you assume...
Posted by: rmdinmd Dec 6 2013, 07:26 PM
the tech manual I have says they work with the lights. the wiring wouldm have to be changed to get them to work without the headlights.
Posted by: toolguy Dec 6 2013, 07:28 PM
As wired by the factory, they can only be energized when the low beams are one. . . I rewired mine to be operational anytime, rather than pick up power for the FL relay from the low beams
Posted by: JawjaPorsche Dec 6 2013, 08:01 PM
J West Engineering has a unit to solve the problem
http://www.jwesteng.com/shop/index.php?id_product=9&controller=product#
Posted by: Kirmizi Dec 6 2013, 08:05 PM
J West Engineering has a unit to solve the problem
http://www.jwesteng.com/shop/index.php?id_product=9&controller=product#
Great product and easy to install
Posted by: ChrisNPDrider Dec 6 2013, 08:13 PM
W/o the aftermarket part or DIY wiring fix the fog lights only work w the headlights on.
I've had the JWest kit w my Pilot "driving lights" for 4 years now and like to drive w these lights on! 
Posted by: Mike Bellis Dec 6 2013, 08:53 PM
The fog light relay gets it's power leg from the headlight switch and it's ground leg from the high beam fuse. When the low beams are on, the relay has power from the switch and the ground through the high beam filament. When the high beams are on, the ground turns positive and the fog relay shuts off.
This is an easy and free rewire without the purchase of an external device.
If you pull the white/blue wire off the high beam fuse and ground it, the fogs will work if any headlamp is lit. If you take the black/blue wire from the fog switch and apply power, the fog lights will work anytime (if you did the previous mod)
NOTE: there are 2 white blue wires on one terminal at the high beam fuse. one goes to the fog relay and one goes to the indicator lamp in the dash. Only disconnect the one to the fog relay and ground it. If you ground both the dash indicator for high beam will not work.
Easy! 
Posted by: euro911 Dec 7 2013, 12:27 AM
Easy!
Posted by: Cap'n Krusty Dec 7 2013, 12:49 AM
As wired by the factory, they can only be energized when the low beams are one. . . I rewired mine to be operational anytime, rather than pick up power for the FL relay from the low beams
The low beam only operation is a DOT regulation ......................... Strange as it may seem, it's common sense, as well. Research has proven that driving with the fog lamps lit in other-than-foggy conditions actually impairs the operator's distance vision. Your eyes become less sensitive to low light levels. SUV, Honduh, and BMW owners where I live are blissfully ignorant of both that and life in general.
The Cap'n
Posted by: Mike Bellis Dec 7 2013, 12:58 AM
Easy!
It's not a true ground. There is a lamp load in the middle. Without a hot on the light wire, the other half of the circuit is a grounded lamp. the relay is grounded through the lamp. When the high beams are on, both sides of the relay coil see 12V. Since this is the same source power, current does not flow, the relay will not function and nothing blows.
This is how the factory wired it! If the lamp was not there, the high beam fuse would blow when the lights turn on -direct short. as long as the lamp can consume the load - no short.
Posted by: jcd914 Dec 7 2013, 01:01 AM
Easy!
Mike is describing disconnecting the ground wire for the fog light relay from the high beam fuse and then taking that the ground wire for the fog light relay connecting it to a ground.
Of course the reason the factory wired the ground for the fog light relay to the high beam circuit was so you could not have the fog lights on when the high beams were on.
Back then they thought people would only want to use fog lights in the fog and high beams and fog don't work together very well. The fog reflects so much light back at you that the high beams make it harder to see. By making the fog lights only work with low beam, in the fog people would use low beams and fog lights together and be able to see better that high beams and fog lights.
Now days it seems every car that has fog lights have them on all the time, fog or no fog, high beams or low beams, day light or not. Does not seem to matter, if they have a light on the front of their car the have it turned on.
How ever you chose to wire your fog lights use them responsibly, make sure the are aimed properly and not blinding on coming traffic.
Jim
Posted by: euro911 Dec 7 2013, 01:43 AM
...
(2) How ever you chose to wire your fog lights use them responsibly, make sure the are aimed properly and not blinding on coming traffic.
Jim
(2) I agree. Seems like maybe eye doctors own stock in the companies that manufacture the new technology headlights ... do we really need to see 1500 ft in front of us at the sake of blinding everybody else coming the other way?
Posted by: Porschef Dec 7 2013, 07:16 AM
I added the Jwest kit (very easy to install btw) mainly to have the ability to signal other drivers via fogs by just using the turn signal stalk instead of waving thru the windshield 
or pulling the headlight switch and rolling them up... 
Works great
Yes I have a bmw with no fog lights 
Posted by: Scarlet75 Dec 7 2013, 07:45 AM
I added the Jwest kit (very easy to install btw) mainly to have the ability to signal other drivers via fogs by just using the turn signal stalk instead of waving thru the windshield
or pulling the headlight switch and rolling them up... Works great
Yes I have a bmw with no fog lights
Of course you do Joe.
Posted by: Cairo94507 Dec 7 2013, 08:40 AM
I think being able to use the fog lights as daytime running lights is great for improved visibility and safety. Not a lot of these cars left, let's do all we can to make sure the SUV's, teenagers on their phones, mom doing her makeup on the way to yoga see us and do not pull out in front of us.
Posted by: old dog Dec 7 2013, 09:13 AM
As wired by the factory, they can only be energized when the low beams are one. . . I rewired mine to be operational anytime, rather than pick up power for the FL relay from the low beams
The low beam only operation is a DOT regulation ......................... Strange as it may seem, it's common sense, as well. Research has proven that driving with the fog lamps lit in other-than-foggy conditions actually impairs the operator's distance vision. Your eyes become less sensitive to low light levels. SUV, Honduh, and BMW owners where I live are blissfully ignorant of both that and life in general.
The Cap'n
Is it my imagination , or is it only us old school mechanics ( not techs ) who know this and bother to find out why ? You are 100% correct Cap'n, my hat is off to you.
Posted by: 1970 Neun vierzehn Dec 7 2013, 08:59 PM
The low beam only operation is a DOT regulation ......................... Strange as it may seem, it's common sense, as well. Research has proven that driving with the fog lamps lit in other-than-foggy conditions actually impairs the operator's distance vision. Your eyes become less sensitive to low light levels. SUV, Honduh, and BMW owners where I live are blissfully ignorant of both that and life in general.
The Cap'n
As we used to say back in the '60s........Right On
Here around Cincinnati, it seems that if you have a fog light switch, it is ALWAYS friggin' ON 
Posted by: Ian Stott Dec 8 2013, 09:02 AM
I did the J west upgrade a few years ago and swapped out the OEM foglights for the pilot lights, aimed them properly and use them as daytime running lights. I feel I am a bit safer safer than before and if I do turn my headlights on at night I can see better and no I am not blinding oncoming traffic as I have everything aimed properly, you do the same and I'm pretty sure you will be happy with the result.
IAn Stott
Moncton
Canada
Posted by: The Cabinetmaker Dec 8 2013, 09:13 AM
For you guys using pilot lights for headlights: Please don't drive behind me. They are blinding in a rearview mirror.
Posted by: Mark Henry Dec 8 2013, 11:36 AM
The fog light relay gets it's power leg from the headlight switch and it's ground leg from the high beam fuse. When the low beams are on, the relay has power from the switch and the ground through the high beam filament. When the high beams are on, the ground turns positive and the fog relay shuts off.
This is an easy and free rewire without the purchase of an external device.
If you pull the white/blue wire off the high beam fuse and ground it, the fogs will work if any headlamp is lit. If you take the black/blue wire from the fog switch and apply power, the fog lights will work anytime (if you did the previous mod)
NOTE: there are 2 white blue wires on one terminal at the high beam fuse. one goes to the fog relay and one goes to the indicator lamp in the dash. Only disconnect the one to the fog relay and ground it. If you ground both the dash indicator for high beam will not work.
Easy!
Long time member Demick did a DIY write-up on this long ago, I did this mod in the early 2000's with his instructions. I don't know if he was the originator of the the pilot fog lights and this mod, but he does deserve the props.
http://members.rennlist.com/demick/fogrewire.html
http://members.rennlist.com/demick/lights.html
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