Fog Light Wiring Q?

[Biggerunn]

So I'll begin by saying that adept is not a word that would describe my ability to read wiring diagrams. I'm trying to understand the fog light wiring diagram in the workshop manual. I would like to wire such that the fog lights could be used with both Lo and Hi beams. It appears the wiring diagram specifies that power to the switch is to come from the Lo beam fuse for USA, and off the license plate fuse for ROW. I'm presuming if I wire off the license plate then the fogs will work any time the light switch is in either the first or second position. However, the terminal 85 wire on the fog light relay runs to ground for the USA (which makes sense to me), but the ROW wiring is shown with the wire running to the Hi beam fuse (which does not make sense to me). Could someone explain the terminal 85 wiring for me?

Thanks.

Mike

[Biggerunn]

To save anyone from having to look this up, here is the diagram. It's the blue/white wire I don't understand. Thanks.

[timmy2]

Euro version does the same thing really, if the coil sees power from 2 sources it doesn’t pick up.
For your choice to have yours work for both hi and low beams on, just use the ground on blue/white and the license lamp circuit for power.
Check your fuse size on license lamp circuit is ok for the new load.

[Biggerunn]

Thanks, Dennis. I was hoping you'd see my post and respond. For my edification, you say that the coil won't pick up if it sees power from 2 sources. Does that mean when the ROW wiring is used, and Hi beams are selected, the fog lights are disabled? So wiring the USA way results in the fogs working only when the Lo beams are selected, but when wired the ROW way, the fogs work with any light switch position except when Hi beams are selected? Would that be why the ROW wiring doesn't simply ground the 85 terminal? Thanks again.

[timmy2]

Sounds plausible to me. But would not work with license lights off

[Cory M]

Check out this thread, Wil Ferch explains simply how to rewire so you can run the fogs whether lights are on or not. I followed the instructions and it worked for me on an SC.

Running Fog Lights only....

[timmy2]

Just have to move the white/yellow wire to a switched power terminal to make them independent of the lights.

Leave the blue/white grounded.

[famoroso]

At one point, I thought I had seen a procedure wherein one moved a wire on the back of the light switch between two different terminals and that resulted in the fog lamp switch being hot at all times (with the ignition on). Does that ring a bell for anyone, or even sound feasible?

For my part, I have deleted the fog lights on my 1987 and I would like to use the fog light switch in the dash to control the factory oil cooler fan. I'd like to figure this out with the least amount of wiring "moves" (or additions) as practicable.

Apologies for the mini thread jack, but figured that if the headlight switch wire swap is a viable option that it could apply to OP's needs.

[Cory M]

Originally Posted by famoroso

At one point, I thought I had seen a procedure wherein one moved a wire on the back of the light switch between two different terminals and that resulted in the fog lamp switch being hot at all times (with the ignition on). Does that ring a bell for anyone, or even sound feasible?

For my part, I have deleted the fog lights on my 1987 and I would like to use the fog light switch in the dash to control the factory oil cooler fan. I'd like to figure this out with the least amount of wiring "moves" (or additions) as practicable.

Apologies for the mini thread jack, but figured that if the headlight switch wire swap is a viable option that it could apply to OP's needs.

That's exactly what I did with mine. See the thread i linked above and my post below. I used the fog light switch and wiring for oil cooler fan, I swapped the switch cap too.

What did you do to your 911 today?

[famoroso]

Originally Posted by Cory M

That's exactly what I did with mine. See the thread i linked above and my post below. I used the fog light switch and wiring for oil cooler fan, I swapped the switch cap too.

What did you do to your 911 today?

Ok, but it looks as if you manipulated wires at the fuse box and not the light switch. I was hoping the changes could be made at the light switch instead.

[Cory M]

Yes, I extended a wire about 6 inches and plugged it into a different port. Not sure if it can be done at the switch, but this works and is easy.