Add turn signals to side marker lights
          by Ken Regenfuse - ken.regen@verizon.net

          First remove the two phillips head screws from the side marker light and pull the light assembly out. You will see two wires attached to the lamp. Cut the black (ground wire) about 1 1/2 inches from the lamp.You will probably have to cut some of the plastic tubing around the wire to get the 1 1/2 inches. In order for this to work, you MUST CUT the wire. Splicing into it will not work.

          Next remove the front turn signal /parking lamp assembly. You will see three wires going to the single lamp in the assembly. Black is ground. On my car green is the turn signal, and the other wire is the parking lamp. Carefully cut about 1/2 inch of insulation from the green wire. DO NOT cut the wire, just the insulation from it, so about 1/2 inch of bare wire shows.

          Next flip up your headlights. Under the headlights you will see a rubber grommet with a wire going through it to the side maker light. Either put a small hole in the grommet or peel a side of it away, so you can feed a wire down through it. This is the wire that you are going to attach to the ground wire of the side marker light that you cut earlier. Again, the wire MUST be attached to the wire going to the bulb, NOT the wire feeding back into the harness.Splice the two wires together and tape them up. If you wish you can solder them as well, but it is not necessary. Once the wires are connected, you can then tape all the wires back up and reinstall the side marker light.

          Now attach the other end of the wire to the green turn signal wire that you cut the 1/2 inch of insulation off of. Again you can solder this connection if you wish, but not necessary. Tape the wires back together and then tape all the wires together for a better seal.

          I know this sounds strange connecting a ground wire to the hot wire of the turn signal, but it really does work. The hot wire acts as a floating ground for the side marker. Once this is done, replace the front parking light assembly. Repeat the same procedure on the opposite side of the car.


          When you are finished, what you will have is this.

          The parking lights and side marker lights will work the same as normal. In the daytime, when you put the turn signal on, the side markers will blink with the turn signal. At night, when you have the parking lights on, and use your turn signal, the side marker lights will blink opposite of the turn signal. Meaning, when the front turn signal blinks on, the side maker will blink off, and visa versa.This will not affect the use of your four way flashers. They will work the same as the turn signals work and side markers work.

          If you really wanted to get carried away, you could do the same thing to the back side marker lights as well! On 99+ M2 models Mazda did not equipped Miatas with as rear parking light. To make them act just like the front markers, you'll need to add a bulb to the rear housing reflector. Follow all the directions as posted above, but instead of wiring the light to the black and white wires of the parking/ brake light, tap one lead of the lamp (vampire connects) into the white wire of the parking/ brake light, and tap the other lead into the green wire of the yellow turn signal light. This wiring method uses the same "floating ground" concept as the front side marker wiring mod, but on both sides of the lamp instead of only one.

          Back To "Tips" Page