Fog Light Wiring
There are several different ways of wiring the fog lights, here I detail the way I do it. If you have a better way, post it below using the comments box.
Some people (on a V8) modify the front fog switch wiring to operate the rear fogs. I prefer to tamper with the original wiring as little as possible, so I fit a new switch. (V6 cars do not have a fog switch anyway so you have no choice but to fit a new one in that instance.)
You need an illuminated switch. It should be visible from the driving seat ideally in order to pass a test. I use an after market one and site it near the regular light switch. You can see where I put it from the picture below:
Such a switch has three terminals.
1) Live in to operate the red LED in the switch, and to feed the switch. (Switch “in” if you like) I take this feed from a front sidelight (some people use a dipped headlamp, but then it tends to go off on main beam). This means the switch will only be powered when the lights are on as it should be.
2) One terminal is an earth, merely to complete the connection for the red LED in the switch. Just take one from the under dash metalwork.
3) The third terminal is the wire that will be fed down to the boot to operate the fog lamp relay that you will fit. (Switch “out” if you prefer.)
In the boot, you will have a relay you allocated for your fog light. This wire down from the switch will go to terminal 5 on your Omron relays. Refer to the relay page for relay wiring.
