Fog light switch wiring problem.

[emilmh]

Heres the quick story;

My car is an 1990 NA6 with optional factory fog lights fitted.
The previous owner did an NB dash conversion but the fog lights werent hooked up to a switch.
In the NB dash i have an unused "window" switch (i presume it locks the windows? in either case its irrelevant) which i would like to use to switch the lights on.
The NB window switch only has two "pins" so when the switch is "on/engaged" the two pins are connected, to complete a circuit.

The problem arises because the plug on the NA harness for the fog lights has 4 pins (while i only have 2 pins on the NB switch i wish to use).

If i can find out what these pins do, i may be able to bypass the 4 harness pins and connect something up to use the 2 pinned NB window switch for my fog lights.
I have attached a photo with the NA pin, and what voltages i read from them at different lighting stages.

Voltages2.jpg

Does someone know what each wire controls? or how i can find out? (i am hopeless at auto electrics)

What i have tried so far is bridging between G and all the other pins in turn, while trying parking lights, normal lights and high beam. None of thsese combos turned the fog lights on. Therefore i suspect that i need to bridge 2 sets of pins to make it work.

I am taking a guess that the switch completes the circuit for the fog light relay (between 2 unknown pins)? and that perhaps the 2 other unknow pins need to be bridged at the same time to provide power to the fog lights?

any help would be appreciated.

[Hammer]

Check this link to see if it helps you with your question - http://www.miata.net/garage/foglights.html

Other info here - http://www.miata.net/garage/garagelighting.html

[Garry]

No idea but just some suggestions.

Did the NA have rear foglights? Maybe one pair of wires is for the front and the other the rear lights. Or did the NA switch have a light in it? One pair of wires may be attached to the dash lighting to light up the switch. Actually I thought the NB8B switch was illuminated? It's been a long time since I looked at the back of my foglight switch but I vaguely remember getting the power for my boost gauge illumination from the circuit that lights up the switch. But I'm old now and my memory is fading so I could be wrong.

Do you have a dedicated foglight fuse? Has it blown? If you were grounding pins randomly you may have blown a fuse.

[Mr Morlock]

I would guess the car was not wired for fog lamps. If you have a set of lamps just follow a normal wiring set up and add a relay and switch- these will be shown on a fog lamp wiring diagram. A Haynes manual probably has a wiring diagram which might confirm if the NA did have any circuit for fogs.