Need HELP with wiring PIAA 540 to OEM Fogs

I have tried to do as much research as possible. Below is a thought that either should work or burn my truck down. Any help to confirm I do not do the latter is GREATLY APPRECIATED Any other suggestions on how to accomplish my goal is also appreciated!

Goal: Use OEM switch to operate PIAA 540 Fogs.

Below is a picture that demonstrates why I am not an artist. Upper left hand corner is right from the instruction manual. To the right is my break out of the PIAA circuit color coded to the harness they supplied in the box and the part of the circuit I am thinking about modifying.

Below the "PIAA Wiring" drawing is a block diagram of the OEM Fog light circuit that came installed in my 2012. The Green and White/Black wires are the stock color of wires going to the OEM fogs.

At the bottom is my initial thought of a way to only cut the wires right at the OEM fogs and then use those to replace the PIAA Switch on their wiring harness. Would this work?

Is my thinking correct that the OEM White/Black wire should be tied to the PIAA Relay white wire and the OEM Green wire should be tied to the black wire of the PIAA relay?




If this works I understand that the OEM fog relay and OEM fuse would also be part of the circuit that now turns on and off the PIAA PL5FB relay. I am OK with this because it allows me to easily go back to my OEM Fogs if I ever need to. Just need to remember it if I ever have to trouble shoot relays and fuses. I also understand they will still retain their OEM function of only being able to be on when low beam is on.

Thank you for any help!!

 

If you have OEM fog lights, just cut and splice the wires at the fog lights and toss the PIAA kit. FYI, the PIAA relay is junk and will crap out in a couple years.

If you have OEM fogs and want to keep them and have the PIAA fogs work in conunction with them, then your splicing to the PIAA relay sounds like a plan. A test light will confirm which wire to splice into.

 

This would be awesome if I could just swap the fog lights and ditch the whole wiring harness. I saw in a couple posts (can't find them quickly right now) but I was under the impression the the PIAA 540 required to many amps for the OEM circuit....?

 

It's probably pretty close. I've run 45W bulbs in each fog light before and I believe the PIAA's are 55W each. Worst case, your lower diagram where you use the facotry fog wires to trigger the PIAA relay is a safe way to get the job done.

 

Follow up from my post. Pugga was dead on to use the OEM circuit! According the 2012 owern's manual the front fogs are 55W. I also reached out to PIAA for their input. I heard back today. They confirmed to just wire the 540 directly into the OEM as their fogs are also 55W.

I know I can check with a DMM but does anyone know off hand if the OEM green wire going to the fogs is the ground wire?

 

I would check with a test light but if the two colors are green and white, I would guess that green is hot and white is ground. Again, a test light would confirm. I'm just going off what I've seen as a common theme with the rest of the wiring I've done on my Tacoma.

 

I ran PIA 55w bulbs out of my 35w rated factory harness until it shorted it out a year ago. Not sure if it was due to overloading or all the swamp water

All I know is I have been to lazy to chase the short down & make sure you caulk the PIA's. They suck........>>>http://www.tacomaworld.com/forum/product-reviews/196375-pia-510s.html#post4294227

 

Interesting , my manual says my front fogs are 42W

 

Anybody confirm or deny this ^^^ ?

 

bump

 

I found this info on page 568 of my 2012 Owner's Manual where they list out the light bulbs. If there is other information out there I would be interested in knowing as well?

Any other input if the OEM green wire is + or -?

 

As it turns out , in my 2009 at least , mine are 42W as it states in my manual

http://www.tacomaworld.com/forum/showpost.php?p=5795261