okay, magnethead the Mechanical Engineer has arrived. Time for everybody to take a seat and wonder if I know what i'm doing, as I explain this in GEICO terms. hahaha. (I'm going to owe somebody a keyboard before this is said and done)




okay, so here's how this giant %$^$&%$ of an electrical system works, starting with the headlamp and fog circuit.

On the left, we have this giant PITA Central Timer Module. It's expensive to replace, and a general PITA. At the top, we have two power sources- ignition-on and constant-on. At the right, we have this fancy little relay that's about to get the life hacked out of it. At middle left, is that column you pull back to **** off the guy in front of you. Bottom left is that dealy that you rotate off-park-headlight to make the lights come on. Bottom right is when you pull that **** out.

So, how do we make the fogs turn on with the parking lamps? Well, if you look ONLY at the fog lamp circuit, what do we have?
We have a 20 amp always-on fuse, which feeds the Fog Lamp Relay. However, if we have power, we must have ground. On this relay, the coil ground (the electromagnetic bundle of wire that humms) comes from the "FOG LAMP CTRL" port of that Timer Module we all hate. The load ground comes from three different places, as there are 3 different loads. The fog lamps are wired seperately, and thus have their own ground. The third ground is for the little indicator lamp next to the rotary ****, that is supposed to tell you that your fogs are on, except nobody knows it's there, since you can't see it. (some indicator, eh?).

The fix, actually, is not very hard. All we do, is ground the coil via the parking lamp switch, and cap off the CTM wire.

 

I'm trying to think of a way to keep the fogs on with the high beams, but i'm just not sure how, without the fogs always being on with the markers. The actual pull switch is a closed switch when off, so to use it, you'd be having a coil energized almost 24/7/365.

having the markers+ fogs as DRL's is as simple as relaying them off of an ignition-on wire in the fuse box, after moving the coil ground per the above.

 

I've been thinking, and I really can't think of a safe way to keep the factory fogs on with the high beams, without using two relays- one to re-route the ground when coil degenerized, another to pick up ground when fog switch is on. The problem with that is that the coil connected inline with the fog lamp switch, will be always-on as long as the fog switch is off (which is when the rotary is in off position). Even then, it's hard to say if it would work.

So basically, my plan is to jump the fog wire to the parking circuit, as shown above. Then, I'll wire in a relay to ignition_on, that grounds that same wire when ignition is on. That way, if key is on, markers and fogs are on.

Then, for the aftermarket lamps, I'll get a floor-mount high beam switch for an old chevy, and mount it up high on the dead-pedal.

Edit- looking at the parking lamp circuit, it looks like the CTM just "passes" the ground through from the rotator switch (Light Green/Red) to the parking lamp relay (Red/Yellow). But since the headlamp switch is probably easier to access than the loom going to the relay/fuse box, that's where it would be easiest to splice in a relay to ground it on ignition-on, plus tap in the fog ground.