I decided that when I did this, I didn't want to have my fogs work anytime the ignition was turned on. I only wanted my fogs to operate when my parking lights (at a minimum), and work independently of my low and hi beam headlights.
While the other solutions worked great for any time, I needed something different. Running wires outside the main fuse/relay panel under the hood was least desirable.
Please see pictures attached below. This is for 2012 models, with the towing package, and the fog relay in the smaller sub-panel. I also am not pre-wired for heated seats.
1. Using a 18-20 AWG stranded
wire, feed it through the edge of the main panel, where the bottom clips into the main body of it. This is directly adjacent to the brown relay at the edge of the box.
2. Untape the main bundle of wires into the smaller sub-panel, and add the new wire to the bundle. Retape as needed, to make it look factory. Super-stealth!
3. In the center of the sub-panel, you can see a small hole. Fish the wire from the bottom, up to the top.
**At this point, the wire is simply run, and not connected to anything**
4. Remove the relay for the Tow circuit. Taking the end of the wire in the main panel, strip off about 3/4" of insulation, and bend the wire in a tight "V" shape. This V is then placed on the spade of the Towing Relay that is closest to the drivers' side fender, and then reinsert the relay into its space. This will be a tight fit.
5. Strip and crimp on a female spade connect to the other end.
6. Follow the rest of the procedure already outlined, and attach it to the fog relay.
I did this method tonight, works great. I felt the same way, didn't want to deal with turning 2 switches off. Thanks for posting this cdh7917