High or low beam switch for fog lights

Few weeks ago, I got some Baja Designs Squadron Pros to go in my Relentlessfab bumper. I wired them into the fog light plugs for ease of installation. But I also wanted them to work with the high beams for road driving or the lows when I have fog light lenses in them. After several hours gathering parts and reading diagrams, I came up with a solution. Instead of tapping just from the low beam fuse like the factory does(pic 1) I put a single pole double throw switch in to take from the high and low beam fuses and feed it back to the fog relay. (Pic 2)


Pic 2




It does require drilling, soldering and disconnecting the battery. Do not work on it with power connected. I accidentally fried my high beam circuit in the BCM from a back feed the first time before installing diodes. That was a $$$ mistake. Gonna try to make this a complete diy but feel free to ask questions and for more pictures.

Parts list:

20ga wire. 3 colors 5-6ft each.
2 Tap a circuit Mini fuse holders. Got mine at Napa. 10a and 5a fuses for each
I got my switches and resistors at a local electronics store. Here are examples I found online
SPDT mini toggle switch
3 pin molex connectors
2 6 amp diodes
2 22-18 butt connectors. I prefer the heat shrink ones but I didnt have any at the time of install.
1 Female insulated spade.
misc heat shrink
electrical tape

Tools:

1/4in drill bit and drill
10mm socket and ratchet
tiny flat head screw driver
Soldering iron
rosin core solder
wire strippers
pliers
crimping pliers
needle nose pliers
razor blade
wire coat hanger (wire puller)
lighter or mini torch ( for heat shrink)
Adult beverage.


I started with the wiring first then moved to the truck. Take your 3 wires and cut about 6in off each one. This will be the short end for the switch and connectors. I used the molex in case I needed to pull the dash and not have to deal with unscrewing the switch. Its optional but saves a headache later on.
Strip both ends. Solder one wire to each connector. Slip on heat shrink over solder joints. Take the other ends and crimp the wires to the pins. You can crimp with needle nose pliers. I like to also solder to make sure its a solid connection. Push the pins into the connector.




I just did them in the same order as the switch so you know which is the center when wiring in the junction box. Stip the 3 other wires on one end and repeat for the connector. Tape the wires up to keep them together when you route them. Here is the results. The center wire goes to the fog relay (1) and the 2 outside wire are for the headlight high/lo tap


Take your tap a fuse ends and cut off the butt connector. I cut mine too short so I suggest you cut right at the butt connector. Also cut a few inches off the 2 wires you are using for the headlight taps. Strip both ends on both. Depending on length, you might want to cut some of the wire off of the diodes. I wouldnt get any closer than a half inch to the diode. Solder the diode to the wires. Make sure the grey stripe is towards the switch wire and away from the fuse tap. For the fuses, I used a 10a on the bottom and a 5 on the top.


Install heat shrink over the diode.


Now for the fun part. Remove the driver bottom floor panel and the panel below the steering wheel so you can access the fog light switch area. Requires 10mm. Now remove the fog light switch from the front cause its almost impossible from the back side. I used a thin oring pick stuck in the top between the switch and panel. It will help push down the tab that holds the switch in. Push from the back side after the pick is in and it should pop out. Disconnect switch. you can feel to the let of the switch hole and there is a gap between the outside of the panel and the edge of the switch. This is where I installed my switch. Drill a 1/4in hole in the center of the gap like so.


Feed the switch into the hole and tighten down. Run wires down to the grommet where the main harness goes into the engine bay. I used a wire coat hanger as a fish tape to pull the wire and it will also pierce through the grommet, so no over size hole and the wire seals. Reinstall fog switch and panels.

Route wires along the outside of the harness to the fuse panel. I went in though the gap on the engine side of the block. Feed wires up to the inside of the panel. You will see the routing a few pics down. Take out the low beam fuse on the right and the high beam fuse on the left. Install taps as shown. Make sure the other 2 fuses in the block between them are the low profile fuses or this wont work. The wire should be on the fender side of the fuse. The engine side is the feed wire.



Strip the matching color ends and use a butt connector to attach the taps. You can see where I cut the tap side wire too short. Keep it as long as possible for routing and flexibility.


Time to set up the fog relay. You will want to pull the fog light fuse relay and bend the #1 tab 90deg out.


Crimp female spade to the wire that is center on your switch. Slip connector over the spade you bent. Re install relay.


This is what it is supposed to look like when done. Tuck the wires out of the way when you put the cover back on. Hook up battery.



Time to test. I set my switch up where when the switch is up, that is high beam mode and vice versa. If you have backwards results, switch the fuse taps.



Hope this helps anyone out there that has wanted to do the same.