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Sat Aug 13, 2005 5:34 pm

Idiot Question #1076: I want to wire my fog lights to the headlight switch so I won't leave them on all night and run down my battery thus making me late for work. How do I do this so I don't burn something up?

Sat Aug 13, 2005 6:36 pm

Remember it is a scan of a 40 year old photo copy.
http://classicvw.org/foglamp.jpg

Sat Aug 13, 2005 7:05 pm

My scans are better!
http://www.thesamba.com/vw/forum/album_page.php?pic_id=80827
http://www.thesamba.com/vw/forum/album_page.php?pic_id=80826
http://www.thesamba.com/vw/forum/album_page.php?pic_id=80825
http://www.thesamba.com/vw/forum/album_page.php?pic_id=80824

If you wire it this way, they only work when the low beams are on.

Sat Aug 13, 2005 7:10 pm

:P :P :P
Mine was given to me by a VW instructor at VW electrical school. :roll:

Sat Aug 13, 2005 7:40 pm

I am not sure I understand what the relay is for. Is it the same relay used to switch between high/low beams? Basically, my original idea was to wire my fogs to the parking light stage of the headlight switch so they would be on when I was driving at night and off when I turn them off. I am just trying to cut down on the toggle switches under the dash.

Sat Aug 13, 2005 7:43 pm

No, it is to carry the load of the fog lights. You dont want all the current of the lights going through the switch that turns them off and on.

Sat Aug 13, 2005 8:03 pm

Ok. Armed with perhaps the most ree-diculous wiring diagram ever, I am back.

This is how I have everthing now... perhaps not off that particular fuse in the block, but you get the point. As you can see, I have no relay in the circuit, but I do have an in-line fuse. Does this make a difference? Where do I get a relay if this is deemed "not good"?

Sat Aug 13, 2005 8:15 pm

the inline fuse makes no difference in the current being draw by the lights.
All the current goes through the switch.
If your system is a 12V system, go to the salvage yard and get a relay from a water cooled VW. They are plugged into the top of the fuse box. Look on the side, and they are marked. The one I use is marked 141-951-253B 40 amp.
That will carry about any current you want.

Sat Aug 13, 2005 10:52 pm

Also if I may. The relay will act as an idiot switch. When you turn your low beams on it sends a 12v "signal" to the relay telling it to actvate the fogs if and only when you turn them on. So you can not run them with out your head lights on and only when they are on low (this way by law). And when you turn off the head lights it removes the 12v signal to the relay and the lights turn off even with the switch to the fogs still on. Also with a relay the power for the fog lights ( main power) runs from your power source to the relay and then to the lights. The power used for the lights (main power) does not and should not run thru the switch. The switch power just tell the relay to let the "main power" go on to the lights.

I will be using relays for my push button switches to operate the acc. But I will only be using the switch as a ground signal to trigger the relay to pass power on to the acc. This should keep any melt downs from happening inthe push button switch.

Hope this helped explain how they work and why you want them. The pics above show just how to install them so follow them and you will be set up.

Kevin

Sun Aug 14, 2005 7:31 am

http://www.radioshack.com/product.asp?catalog%5Fna...=275%2D226

I used this relay to wire the fog lights on my Westy. Small, cheap enough with plenty of load capacity. Works fine and you can find a Radio Shack almost anywhere.

Sun Aug 14, 2005 7:48 am

Mark~ From the pic I can not tell fromthe top scematic if it will work how he wants it. Can you have the head lights triger the "on circut" in the relay so if he forgets to turn off his fogs but does turn off his heads he will be ok?

That is a great price and 30amps should be plenty for any fog/driving lights.

Kevin

Sun Aug 14, 2005 8:02 am

Yep, It'll work. I basically wired it like the last schematic Everett posted (except on my T2). Main power goes directly to the relay. SEcondary power goes thru the switch. They way I did it my ignition has to be on to power the switch so no issue with forgetting to turn them off and killing the battery :x The good thing is the relay is so small it's easy to mount/conceal which on the bus is more of an issue due to the small confines bedind the paneling. As a side note to Jim...don't be embarassed....I had to ask around to as electrical is NOT my strong suit. But it was really simple. If I can do it.... :wink: More info here.
http://www.carcentral.net/content/guides/HowToInstallAuxiliaryLights.php

Sun Aug 14, 2005 8:52 am

As a side note, my sone had one of his Ricers stolen. He is into electrical.so he was trying to figure a non obvious anti theft relay into his system. He wanted to kill the electric fuel pump without an obvious switch, which the theives look for now days.
Since he doesnt smoke, his relay is grounded when you push in the cigarette lighter. :D

Sun Aug 14, 2005 10:39 am

Russ Wolfe wrote: As a side note, my sone had one of his Ricers stolen. He is into electrical.so he was trying to figure a non obvious anti theft relay into his system. He wanted to kill the electric fuel pump without an obvious switch, which the theives look for now days.
Since he doesnt smoke, his relay is grounded when you push in the cigarette lighter. :D

Smart idea. Hide it in plain sight. I am currently looking to do a kill switch on the Westy to kill power to the coil. But finding a location to hide it is somewhat of a challenge. I will probably end up hiding it....well perhaps I shouldn't say exactly WHERE :wink: 8-[ And Russ...my son used to drive a Honda ](*,) then he saw the error of his ways and sold it. He said he was tired of the wrong kind of attention being paid to it.

Sun Aug 14, 2005 11:35 am

He did get the car back but in not the best of shape.
http://www.wolfenet.org/gallery/stolen
Since he is a ham radio operater, his cars now phone home if stolen. A kinda home brew Lo-jack, with GPS and a 2 meter transmitter.

Sun Aug 14, 2005 12:54 pm

Hide a kill switch in the boot for your E-brake. THats where a buddy of mine did and he just had to feel through the rubber and hitthe switch and nobody ever saw it... Though having been originally from CA, I can tell you that if your car is nice enough and someone wants it bad enough it WILL get taken. I seem to remember some cars taken off the line at BOR several years ago. Lame bastards!

Anyway, I am going to avoid another car fire and use the relay set up as advised by Russ and Mark. So where doe the power to the relay(and thus the fogs) tie into the headlight circuit? Also, is there any certain gauge wire I should be using and what about a switch for the fog relay? Do I use a toggle ?

Sun Aug 14, 2005 8:36 pm

jimmynotch wrote: Anyway, I am going to avoid another car fire and use the relay set up as advised by Russ and Mark. So where doe the power to the relay(and thus the fogs) tie into the headlight circuit? Also, is there any certain gauge wire I should be using and what about a switch for the fog relay? Do I use a toggle ?

I used a toggle rated for 30 amps and 14 gauge wire. You could probably go with 16 gauge or down to 12...I tied my hot into the main fuse box not the light switch so someone else will have to help on that one...

Sun Aug 14, 2005 8:38 pm

If you wire like the schematic that Everett and I posted, everything will work fine. Whether you use a toggle or a push/pull switch doesnt matter.