DIY Fog Lights for MK III Golf/Jetta w/o factory fogs
I have a '97 Jetta GL, and I was interested in getting factory fog lights. However, I didn't have the factory wiring harness to do so, nor did I have the switch located in the dash. I bought the North American switch and 2 sets of fog lights from a fellow member.
The following were the items I used, and that you'll need:
1) Soldering Iron
2) Head Gun or a lighter
3) Small diameter shrink tube
4) Small snips (wire cutters)
5) Rosin Core solder
6) 1 (one) yellow ring terminal
7) 16 Gauge wire
8) Crimp tool for crimping ring terminals (if possible)
9) 30 Amp relay for Fog lights and a 15 Amp fuse or greater
10) North American Fog Light Switch
11) Electrical Tape
Remove the dual dummy panels within the bumper, and gently place each fog light into it's designated location to measure wire.
On the passenger side, I measured out a ground wire to be long enough to travel to the battery, and a positive wire long enough to go to the round connector located under the rad shroud. I cut back a portion of each wire, "tinned" the wire, and cut a piece of shrink tube long enough to cover the wire and the fog light connector. When looking at the back of the fog light, the ground is the top connector, while the power is the bottom. Although it doesn't matter, I chose to do it like that. You can open up the light to double check, this is the same for both lights. I repeated this step for the drivers side fog light.
When looking at the round connector, the Grey w/ Yellow stripe is the power for the fog lights. If you either cut the wire, or remove a portion of the casing, you can twist and solder the two power wires for each fog light to the bare powe wire. Make sure you have enough wire, because in this case it might be better to have a little too much, than not enough. After soldering the 3 (three) wires together, I used electrical tape to seal the wires, and reused the split loom to cover all of the wires up.
For the two ground wires, I twisted them together and crimped them inside a Yellow Ring terminal (10 to 12 gauge wire) and put a piece of shrink tube over the end, and used electrical tape to further seal it.
I tried to run the wires from each fog in an "out of the way" area, and zip tied the wires in a nice and clean manner.
I purchased a relay from my local Radio Shack/The Source (in Canada). It was an "Automotive Relay", rated @ 30 amps. Cost me appoximately $11.75 CAD. This relay plugs directly into the #10 relay slot, known as the Fog Light Slot. Also make sure to have a 15 amp fuse or greater in the Fog Light fuse slot for this system to work.
For the final step, I switched out my stock headlight switch for the North American Fog Light switch. Where'd you normally twist the lever clockwise to activate your marker lights and dash lights, you'd pull the lever out to activate the Fog Lights on the North American switch.
If your fog lights came with mounting hardware (ie. bolts to secure the housing in the bumper) your set. My lights didn't, so I'll have to get some 1/4" bolts and lock nuts to secure the housing inside the bumper. Middle dummy panels can also be purchased from the dealership, or the local junk yard. This job took me approx. 1.5 hours with the tools listed above. Should you not have all of the tools, it might take you a little longer, provided you have soldering and electrical know-how. An interesting thing to note as well is that my fog lights stay on with the Low and High Beams, and I'm not 100% sure if they are supposed to do that or not.
