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Discussion Starter #1
After a little puddle hopping this morning I smelt a burnt rubber smell. didnt think too much since I was just going for coffee with my wife. once I got in the driveway holy crap my wiring harness from my PIAA 510 fog lights was literally on fire. Fuse didnt trip so I ran and got my sidecutters and snipped the + off the battery. What a sketchy situation. I know this isnt a common occurance but the wiring is premade and just plugs in. The switch source was taken off the switched lowbeam wire on the driverside headlight. Any thoughts on how or why this happened? PIAA Corp is obviously closed for a few days now so I cannot contact them.
Some insight will give us a little peace of mind since we are headding away for the holidays in the FJ but my wife thinks it is still going to burn down.
 

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Discussion Starter #2
I should also note that the light in the PIAA switch never worked, red/green LED never functioned and I never thought to question it...
After taking a closer look, it seems the wires overheated then caught fire cuz it is completely melted from the relay down to the lights.
 

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The fuse should have blown.
Keep us posted on what you find out.I have the same kit and the switch light does work so maybe a relay problem??
 

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The fuse should have blown.
Keep us posted on what you find out.I have the same kit and the switch light does work so maybe a relay problem??
I am hoping this was just a case of something defective. I am getting ready to order a set of the 520's next week. :(
 

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Discussion Starter #6
It is the regular 20A that comes with the harness
 

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So it was the wiring from the relay to the lights. It sounds like a direct short to ground but did you have the fog lights on or off. Also did it burn both right and left side wires to the lights?
 

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Discussion Starter #8 (Edited)
The lights were Off and it is both left and right sections of the harness that are fried.






 

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The only thing that I can come up with is that the relay shorted out or broke internally and completed the circuit. Because if the switch is in the off position the relay is in the open position. One other question was the relay fully connected to the plug and was there any burn marks on the relay terminals?
 

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I had a issue with my PIAA 510 fogs also, one day they just didnt turn on, so 1st thing I did was change a blown fuse, but every time it would reblow the fuse. Then I changed the relay and it kept blowing out. I had to take it to a professional , they found a wire inside both lamp housings had came loose and grounded to the metal inside. Ive never had a issue with KC, and they are A LOT cheaper.
 

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Discussion Starter #11
Well, i just stripped the harness out and it was ONLY the passenger side of the harness.


 

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Discussion Starter #12 (Edited)
These lights came from James with my Expedition One front bumper.

For warranty purposes,should I be disassembling the relay?
Actually, the relay looks fine, maybe discolored a lil dark but not melted
 

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Sorry to hear about what happen to your PIAA harness.
I have the PIAA 520 SMR's and 4 set of Hella micro DE's.
Will all these directly wired/always hot wiring harnesses, I mounted a 10mm wrench at the battery bolt holder for quick access (to a tool) to disconnect the negative battery cable if needed.

 

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If you say that your install was correct and properly done than just return it to them and get another harness and call it a day. but you said that the switch light never worked are you sure that you had all of the wiring in the correct location and the switch grounded? A wiring harness just doesn't burn apart with out a reason so I would be checking all of the install that you did. Do you hear anything loose in the rely?
 

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Discussion Starter #15
The install was exact per the schematic. the system was grounded to the chasis ground and the Switch power was installed with the supplied connector from PIAA to my low beam 12V source. nothing is loose in the relay. Even if it went to ground, the fuse should have blown killing the power.
 

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Discussion Starter #16
I am calling it the day, we have a 3 hour trip ahead of us and have her convinced we wont/cant burn down on the highway.
Thanks for the input ( I will deal with this after the holidays). Merry Christmas and play safe!

bob
 

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The fuse should have blown.
Keep us posted on what you find out.I have the same kit and the switch light does work so maybe a relay problem??
The fuse won't blow if the ground is shorted to 12v, and the power is shorted to ground (polarity reversal), or both wires are hooked to power. This goes around the fused side of the relay, and will melt the wiring.
 

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Has nothing to do with the relay or switch. If it did then the relay or switch would be melted.

Wherever the most insulation is burned away is most likely where the short occurred.

All it takes is one little loose strand of wire to start the short, melt the insulation and turn into a small fire. Good to hear that you caught it in time.
 

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Has nothing to do with the relay or switch. If it did then the relay or switch would be melted.

Wherever the most insulation is burned away is most likely where the short occurred.

All it takes is one little loose strand of wire to start the short, melt the insulation and turn into a small fire. Good to hear that you caught it in time.
The lights were not on at the time of the melt down so the only location that it could have received the power from would have been the relay area. And a bosh relay can handle up to 30 amps no problem with there interior parts so the 16 gage wire will melt before the relay will fry a electrical short will take the easiest path to ground.
 

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Hi Guys!
I have Piaa 520s and 60XTs installed in my Fj using the Piaa supplied harnesses and switches.The lights on my switches have both worked from the day of installation although one is brighter than the other. Canadian_Rocks reported that his switch light never worked. I am curious if this in someway indicated a short from the beginning.
Marc
 
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