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boxsterfan
Are the fog lights supposed to work independent of the headlights?

Mine never come on unless the headlights are on.
michael7810
Mine come on with the parking lights or low beams.
Bob L.
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...
rmdinmd
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.
toolguy
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
JawjaPorsche
J West Engineering has a unit to solve the problem

http://www.jwesteng.com/shop/index.php?id_...roller=product#
Kirmizi
QUOTE(JawjaPorsche @ Dec 6 2013, 06:01 PM) *

J West Engineering has a unit to solve the problem

http://www.jwesteng.com/shop/index.php?id_...roller=product#

agree.gif
Great product and easy to install
Chris Pincetich
agree.gif
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! beerchug.gif
Mike Bellis
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! smile.gif
euro911
QUOTE(Mike Bellis @ Dec 6 2013, 07:53 PM) *
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! smile.gif
Huh? I haven't looked at the schematic, but wouldn't grounding a hot lead short the circuit? I'm not getting it, Mike confused24.gif
Cap'n Krusty
QUOTE(toolguy @ Dec 6 2013, 05:28 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


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
Mike Bellis
QUOTE(euro911 @ Dec 6 2013, 10:27 PM) *

QUOTE(Mike Bellis @ Dec 6 2013, 07:53 PM) *
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! smile.gif
Huh? I haven't looked at the schematic, but wouldn't grounding a hot lead short the circuit? I'm not getting it, Mike confused24.gif

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.
jcd914
QUOTE(euro911 @ Dec 6 2013, 10:27 PM) *

QUOTE(Mike Bellis @ Dec 6 2013, 07:53 PM) *
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! smile.gif
Huh? I haven't looked at the schematic, but wouldn't grounding a hot lead short the circuit? I'm not getting it, Mike confused24.gif


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

euro911
QUOTE(jcd914 @ Dec 7 2013, 12:01 AM) *
(1) 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.
...

(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
(1) OK, makes sense now.

(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? screwy.gif
Porschef
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 slap.gif or pulling the headlight switch and rolling them up... dry.gif

Works great

Yes I have a bmw with no fog lights rolleyes.gif
AndyB
QUOTE(Porschef @ Dec 7 2013, 08:16 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 slap.gif or pulling the headlight switch and rolling them up... dry.gif

Works great

Yes I have a bmw with no fog lights rolleyes.gif


Of course you do Joe. slap.gif
Cairo94507
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.
old dog
QUOTE(Cap'n Krusty @ Dec 6 2013, 10:49 PM) *

QUOTE(toolguy @ Dec 6 2013, 05:28 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


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.
1970 Neun vierzehn
QUOTE(Cap'n Krusty @ Dec 6 2013, 10:49 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 biggrin.gif Here around Cincinnati, it seems that if you have a fog light switch, it is ALWAYS friggin' ON ar15.gif
Ian Stott
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
TheCabinetmaker
For you guys using pilot lights for headlights: Please don't drive behind me. They are blinding in a rearview mirror.
Mark Henry
QUOTE(Mike Bellis @ Dec 6 2013, 09:53 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! smile.gif


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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