light switch mod/ what wires on my set up

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Blackwater

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OK Started the light switch modification this evening. Very straight forward and everyone that posted their mods it was a great help. BUT after using information from here, information from web searching I have hit a brick wall.

My wiring is not like any I have seen in these or other post and web sites. I think I have over looked or am confused. Idk but this is what I got.

I have the switch that you have to turn the knob to remove the switch unit. That was done. I pulled apart the unit without cutting off the faceplate. “I dont understand why cutting the faceplate off is needed”. I chopped down the ramp. Now the guide arm that slides over the ramp is different then what I have found in photos. It has a spring within the arm with a white pin that slides within the clear housing and over the ramp. The switch I have put back in and it works fine but still cant turn on the fog light other the with the headlights being on. The switch will still pop out in running light mode but wont turn anything on. Doesnt pop any fuses.

The brick wall is the wiring. I have to 3 plugs, 2 for the headlights and 1 for the dome lights. On the 2 for the lights There are only 7 spots one both plugs and only 6 wires in each. Nether have a white and black wire but the one plug that is gray “i think” has a brown.

What wires do I tie into? Or what colors on my set up?

Also in peoples post and write ups it is unclear as to the splice and cut. Someone posted no cuts needed then said cut wt/bl and splice into brown.

When cutting the wt/bl wire do you just cut the connection it made totally then tie it into the brown? Do I leave the brown in its present spot adding the wt/bl or disconnect the 2 from the plug and tire them together not entering the switch at all?
 
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Blackwater

Blackwater

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Ok found out that the connection is made BETWEEN white/black and brown. Going to hunt for the wt/bl wire now
 

ELVATO

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What so what are you trying to do? You're trying to do the mod where your fogs turn on without turning on your headlights (which I take means you have a pre 03 Expy)? Can you post a pic of your plug and connectors?
 
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Blackwater

Blackwater

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its a 99

Yeap thats it. I want to run the fogs without the headlights. I will get a photo asap posted. There is however a white then white and black running into the dimmer, idk?
 
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Blackwater

Blackwater

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Why cant I post photos into this thread? Code works in other post.......
 

lakmflx

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Looks like you are posting the web link for ur pic instead of the IMG code. Try the code that starts with
 

walnuts4x4

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ok i've been looking but anyone have the entire link to this mod? I am thinking about doing it
 
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Blackwater

Blackwater

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Yeap Im putting in the right code. They work fine in other post but for some reason when I copy and paste them submit the code changes. I tried a few times. IDK
 

Mike00~07

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Use a test light to find the wire that powers the fog light realy when swtich is used normally. Thats the wire you want to splice into either the brown wire or KOEO wire. ( key on enging off)

On my EXPY I had to cut the fog light wore that went to relay. if I didnt everytime I would turn on fog lights with headlights, it would pop a fuse. Cut the white/black wire and spliced it into the brown wire and works good now.

Can see more pictures in my Sig....
 

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Blackwater

Blackwater

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Finally got around to messing with the wiring on the switch. Found that the yellow wire controls my fog lights.
Now here is another problem. The brown wire works when I tie into it and will turn my fog lights on when in the Park/Running light position. But now they WONT come on with the head lights. They come on in the Park/Running and Hi beam and not with Low beam....

Ideas?
 

Tjhoward84

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Thread revival. I've had this mod done on my 1999 Expedition since 2006 and it's worked flawlessly. I recently changed the bulbs in my fog lights back to to the original halogens. During the bulb swap process something blew fuse 27 (5A) under the dash that runs the relay and fuse 9 (15A) in the main fuse box under the hood. After replacing both blown fuses, the fog lights work in both the Parking Light and Headlight positions. However, the headlights now come on when the switch is in the Parking Light position. Removing the wire that was splices between the brown wire and the white/black wire returns everything normal operation. But my fog lights only go on with the headlights - per the factory setup.

I'm wondering if I did something to the Parking Light or Headlight Relays that are allowing the headlights to come on when the light switch is in the Parking Light position.

Anyone experience this issue and if so, how did you fix it?

This is on a 1999 Expedition with DRL and Auto Dim for the instrument cluster.
 

Anthony DeVor

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Thread revival. I've had this mod done on my 1999 Expedition since 2006 and it's worked flawlessly. I recently changed the bulbs in my fog lights back to to the original halogens. During the bulb swap process something blew fuse 27 (5A) under the dash that runs the relay and fuse 9 (15A) in the main fuse box under the hood. After replacing both blown fuses, the fog lights work in both the Parking Light and Headlight positions. However, the headlights now come on when the switch is in the Parking Light position. Removing the wire that was splices between the brown wire and the white/black wire returns everything normal operation. But my fog lights only go on with the headlights - per the factory setup.

I'm wondering if I did something to the Parking Light or Headlight Relays that are allowing the headlights to come on when the light switch is in the Parking Light position.

Anyone experience this issue and if so, how did you fix it?

This is on a 1999 Expedition with DRL and Auto Dim for the instrument cluster.

So no you didn't change anything it is causing the circuit to BACKFEED. Meaning you have essentially wired your headlights to your running lights because the fog lights used to only come on from the headlights so it had circuit from the low beams to the fog lights and now that the wire that feeds the fog lights is tied to the running lights it BACKFEED the wire that feeds the fog lights from the low beams. Hope that helps and you understand it.
 
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