wiring fog light switch

Hi, I am attempting to wire a switch to turn on my foglights. I have a 2008 toyota corolla that is prewired to install foglights. I have connected the lights to the existing wiring harness and installed the relay in the correct position. The relay is a 4 lead relay with the pins 30, 85,86,87. I have an aftermarket push switch that came with the foglight kit. It has 3 wires coming out of it, a power, ground and acc. A person who did an install with the same kit used the ground and one other cable to connect it to a cable behind the relay. They have no idea which cables they connected and i would like people who have experience to guide me through it. I have read alot and think that i can connect the acc cable to the cable behind the 86 pin on the relay and just ground the switch. Will that be sufficient? If possible diagrams would be best thanks for your help!

the way i think i personally would wire it is like most factory systems.

30 from fused power directly from the battery or power post in engine compartment.

87 to the lights.

86 tapped into the "low beam" wire from the headlight switch

85 to the "acc" of the switch

ground the terminal that is labeled "power" on the switch.

with that layout, the foglights can only work when the headlights are on low beam AND the switch is turned on.

OR....

connecting 86 to a parking light (not the low beam) wire would instead let you run the fogs any time the parking OR healdights are on. either way the headlight reminder will keep you from killing your battery by leaving your lights on by accident.

if you want the light inside the switch to light up, the wiring might be like this...

same as my first suggestion except, ground 85 and run 86 to the "acc" of the switch.

put 12v (preferably from a "keyed" source to prevent the battery kill) to the "power" of the switch.

run a ground wire the "ground" terminal of the switch.

this way the you key will shut them off and the switch will be lit.

yuk

quiet rural missouri, near KC.

If your system moves you physically and not emotionally, you have wasted your money.

i think the second way is the way its supposed to be wired. I currently have a randomly working system. I connected it this way because i didnt know what to do, and one day in the car i pushed the switch and it worked, so i left it like this; My acc is connected to the ACC behind the head unit. Power to pin 86 of the relay and the ground wire grounded. Are you able to put up a diagram of the switch connected to the relay for your second suggestion?

it sounds like you are close ... if you were to switch places with the two wires on the switch and then run a ground wire to the ground terminal on the switch, then the switch light wuld work all the time the key is on.

if you didnt switch the two wires, the switch will only light when the fog lights are turned on with the key on.

as for the randomly working part ...  it may be a bad connection, weak relay, lame switch, or somethin else. how did you connect it to the radio wiring?.. please dont say you used a scotchlock.

make sure the terminals you use on the switch have the plastic or rubber covers over each of them so they can short out against each other.

yuk

quiet rural missouri, near KC.

If your system moves you physically and not emotionally, you have wasted your money.

i just retried to connect it. I pulled out the relay and it looks like its melting a little. Im still doing something wrong. which bloody sucks. For my amp and sub wiring most are soldered on or crimped. But with the headlights it was random so its just electrical tape. atm im not too fuss about getting the actual switch light to turn on, because the forlight indicator on the dash turns on. What im aiming to do is have the dash indicator on with the foglights on when i push in the switch everytime.

electrical tape is an insulator, not a connector.

without knowing things like vehicle, lights, switch and relay brands and models numbers. and knowing what size wire you are using throughout, i dont feel that i am being givin enough information to help you to a safe and satisfactory outcome.

if the relay is melting, something MAJOR is incorrect and if something is done on the "cheap" like improper wire or correct relay size, proper connections etc .... hooking it all up may be more of a fire/wiring hazzard than anything.

my advice at this point is for you to find a competant automotive electronics professional to make sure you are using ingredients that will lead to a functional outcome. and not disaster.

yuk

quiet rural missouri, near KC.

If your system moves you physically and not emotionally, you have wasted your money.

I did not read the other posts.  But I can tell you about your switch and relay.  The switch is an illuminated switch. The ground is there only to supply ground to the lamp in the switch.  The switch has to be connected like this.  Ground connection needs to be grounded.  Connect the power connection to a wire that has 12volts on it either when the key is on, or the low beams, if you only want it to come on with the low beams.  The Acc connection needs to be connected to terminal 86 of the relay.  Ground terminal 85 of the relay.  Connect terminal 30 to the battery via a 10Gauge wire, and a 15 amp fuse AT THE BATTERY.  Connect the lights to tereminal 87 of the relay.

im not sure what happened to my latest reply. It had all the information about the relay i was using and pictures of my switch. I have it working now, all i needed to do was have the parkers on when i turn the foglights and they turn on and off whenever i need them to :D

oh yeah, i would also like to thank everyone for their input and help on this! especially its yuk. thankyou!

groovy.

yuk

quiet rural missouri, near KC.

If your system moves you physically and not emotionally, you have wasted your money.