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Discussion Starter #1
I can do most anything when it comes to adding accessories and getting around tough problems but i cannot do wiring. It always seems to escape me. My probelm is I have an OEM aux switch and harness and PIAA 540 fog lights and its wiring. I would like to use the OEM switch for asthetics but I cannot figure out the wiring that is required to connect into the existing PIAA harness. Is the PIAA relay required? Does the OEM switch and harness go to the fuse panel and if so where does it plug in or do you need a blank slot. How and where do you connect the PIAA wiring with the harness?:mecry:

I have been through all the threads i can find but there does not seem to be an abunandance of options going this route. I am a very visual person so if you have pics its worth a thousand words to me but i will take any help/suggestions.

Have mercy on me i know some of this maybe stupid questions but...

Thanks for any help
 

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If you have the factory switch and the harness that goes from the switch to the plug behind the drivers kick panel, then do the following if you want to utilize the factory wiring:

1. Buy Toyota Aux light relay and a fuse. Both go into the engine bay fuse box and are clearly marked.
2. Install switch and harness. Almost plug-n-play but you will need to tap into the back light circuit of one of the other switches to get the new switch to light up with the headlights.
3. In the engine bay on the drivers side front fenderwell close to the brake master cylinder is an unused plug. This is where the output of the Toyota relay shows up. You need to connect the + and - wires from the fog lights to the two wires in that connector. You can buy the correct harness from Toyota but you may still have to adapt at the lamp end. Or you can cut off the previously mentioned connector and splice the wires that came with the fog lights to the wires that went to the connector. Note you will only need the wires coming from the lamps. This is generally a "Y" cable with 2 wires from each lamp that connect to each other with the 2 wires of the 3rd leg of the "Y" going to ground and the output of the PIAA relay. Cut off the PIAA relay and trim the ground to match and splice these 2 wires to that unused connector and your good to go.

If the harness you have does not go to the kick panel connector then you will need to use the PIAA relay and harness and connect that directly to the Toyota switch.
 

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Discussion Starter #3
Problem Solved....Thanks for the help! I just needed some pointers and i got it up and running.
 

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If you have the factory switch and the harness that goes from the switch to the plug behind the drivers kick panel, then do the following if you want to utilize the factory wiring:

1. Buy Toyota Aux light relay and a fuse. Both go into the engine bay fuse box and are clearly marked.
2. Install switch and harness. Almost plug-n-play but you will need to tap into the back light circuit of one of the other switches to get the new switch to light up with the headlights.
3. In the engine bay on the drivers side front fenderwell close to the brake master cylinder is an unused plug. This is where the output of the Toyota relay shows up. You need to connect the + and - wires from the fog lights to the two wires in that connector. You can buy the correct harness from Toyota but you may still have to adapt at the lamp end. Or you can cut off the previously mentioned connector and splice the wires that came with the fog lights to the wires that went to the connector. Note you will only need the wires coming from the lamps. This is generally a "Y" cable with 2 wires from each lamp that connect to each other with the 2 wires of the 3rd leg of the "Y" going to ground and the output of the PIAA relay. Cut off the PIAA relay and trim the ground to match and splice these 2 wires to that unused connector and your good to go.

If the harness you have does not go to the kick panel connector then you will need to use the PIAA relay and harness and connect that directly to the Toyota switch.
After reading this, I'm feeling like I want to just pay Toyota to install the fog light option and then replace the Toyota lights with PIAA. Of course, I say that until I ask what Toyota charges. This may turn out to be my next DIY to save $$$$.

-FJ Florida-
 
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