Hi folks.
Can't seem to find the answer here, but would anyone know how I can re-wire things so that I can operate my fog lights without having the main headlight switch on?
Thanks
J.

 

Pretty simple to wire up a light switch. Have you looked for a wiring diagram online? If you can't find one, post here and I'll figure out where I have seen them. There are multiple sources.

I am assuming you'll want to keep the original switch.

 

Volvo Wiring Diagrams

My 2002 V40 is able to have the foglights operating with the park lights only activated if one does not wish to have the headlights on also. (low or high beam)

The rear foglight on the drivers side however only works if the headlights are on also.

 

I'd use a relay and a lighted on off switch. The power wire from the battery to the relay to the fog lights should be as short as possible as it has the major power draw.

 

Thanks for all the replies, especially the link to the wiring diagrams.
Seems like the only thing I need to do is run 12v on the fog light bridge connector. ( it gets its 12v from the headlamp switch when it is on)
So, does anyone know where that item lives?
Txs
J.

 

This is my favorite, but the diagrams are correct for a 95. A 97 might be somewhat different.
Volvo 850 Maintenance And Service Documents

On the diagram, you can see that there is a violet wire running from the headlight relay to the fog light relay (through the bridge). I assume (have to assume, based on the diagram) that wire is only hot when you have dim headlights. I don't really see any other way it could work.

So the headlight relay and the "bridge" are both supposed to be in the central electronic unit. As it happens, I just cut one out of a 97 last week, but I don't know what a bridge is.

I found this purple wire. The headlamp relay is on the upper face of the CEU, I assume you can find that. The fog lamp bridge is at the bottom left of the inside portion, left if you are looking at the relay side, not the wire side.

Not easy to get to. Since I was looking at a 95 wiring diagram, I would not assume 100% that is the right wire. As always, splice it back together if it's not the right one, ha ha.

 

I found the fog light bridge. It has a big "213" on it, and it is just a jumper. You could remove it and run power into the front of where it was, to light up the pink wire coming out.

That ought to do it. Wouldn't have to cut anything.

 

Thank you for the service manual references. very useful.
I assume the "bridge" is on the under side of the CEU, and that I would need to remove the interior kick panels under the dash to access.
Correct?
Txs

 

The bridge is on the bottom row.

To see the inside part of the CEU, you do have to take out the panel that hangs under the dash. I don't know what it's really supposed to be called.

 

Found the fog bridge. Thanks for that. I also know where I need to put the 12 volts.
My last question is...Where is a good and convenient place to grab 12V. I think I want it to be 12v that is only there when the ignition is on.
Suggestions?
Txs

 

Just to complete this thread, I grabbed the 12 volts from connector bay 24/21 the green 12 pin connector. Took the 12v from pin 12 (yellow-Violet). Goes to the cigarette lighter fuse.
Now to complete the project I plan on putting some CREE H3 LED lamps and then just run these as a daytime running lights.
Txs all.

 

Sorry I am late. Here is a post from many years ago using the factory switch.

https://volvoforums.com/forum/volvo-...ng-help-41438/