Foglights with Parking Lights

also Foglights with High Beam
by John Moore

Performed on a 92 Stealth TT - others may vary

There are two parts to this mod. The first is to keep the foglights on when the high beams are on. This can be personal preference but it's also important if you want to do the second part of the mod - fogs with parking lights. These steps retain all switch operation and doing it this way makes sure the fogs go off when the lights are turned off - no accidents that lead to a dead battery.

Keeping the fogs on with high beams

  • Remove the gauge trim panel so you can get to the foglight switch wiring. There are two screws at the top; then the bottom just pops off.
  • Locate the wiring harness for the foglight switch.
  • Cut the wire in the top left corner of the harness (see illustration), leaving 1-2 inches of wire at the plug to connect another wire to. Tape up the harness side of the wire you cut because it gets +12v when the high beams are on.
  • Run a wire from the plug to a ground source. This can be a new ground wire that you run, or for a quick and easy ground source you can use a wire from the dimmer harness below. Splice into the solid black wire (see illustration) and run a wire from there to the wire you cut in the previous step. This provides a constant ground to that terminal of the foglight switch.

Fog lights with parking lights

  • This part takes you under the hood. Locate the relay box on the passenger side in the front.
  • Remove the three 10mm bolts that hold the box to the car. You may need to remove on of the IC hoses to reach a bolt.
  • Snap the cover off of the bottom of the box, exposing the wires that go to each relay.
  • Remove the relays marked FOG and TAIL.
  • Using the diagram above, cut the proper wire leading to the bottom left terminal of the FOG relay, leaving enough wire on the relay side to connect another wire to.
  • Tape up the other end of the wire you just cut.
  • Now you want to tap this wire into the TAIL relay at the position shown. Working on the underside of the box, splice a wire from the TAIL's center terminal wire to the FOG relay's lower left terminal wire as shown in the illustration.
  • Snap the bottom cover back on, bolt down the relay box, and you're done!