Wiring Lights on the Tow Vehicle

[BYOB Fishing]

Hi all,

I am trying to put a set of PIAA fog lights on my 2006 Jeep Grand Cherokee. The PIAA kit came with good directions, but when it comes to the powering of the switch, I am a bit confused. The directions just say to connect it to a power source that is only on when the low beams are on. The only thing I can think of is the actual wire that is running to the bulb itself...I'm just wondering if that is a poor practice, connecting the wire directly to the headlight bulb power.

I did some reasearch here: https://www.4wheeloffroad.com/techarticles/electrical/131_0906_off_road_hid_headlight_wiring/index.html

and point #7 seems to say that it's OK to do this, but I am not interested in tearing up my vehicle; I want to make sure first.

Any thoughts?

Thanks! Matt

 

[Captain Ahab]

A power source that is only on when the low beams are on? I thought the low beams stay on even when you turn on the high beam?

So that would mean a power source that is only on when the headlights are on, right? You can pull that from the wire running from the headlight switch.

 

[BYOB Fishing]

I thought the low beams stay on too, until I tried it. When I flipped the brights, the low beams went out. I guess it's some law to only have fog lights on when the low beams are on.

On this Jeep, the light switch is on the column, activated by turning the end of the turn signal lever. I have no idea how to locate that wire, and even if I did, it would be a smaller gage than the wire I would be splicing it to. Would that be a problem?


I hate cars...

 

[huntinfool]

Years ago when I was with our local volunteer fire dept. I wired up my and several other vehicles with wires for emergency lights and one of them was called a wig wag. It made the head lights alternately flash, and I had to wire it in on the actual wires to the headlights. It never seemed to affect anything. They worked for years and when I took them off to put on another vehicle the headlights still worked.

I'd say will be fine. But that is my opinion.

 

[BYOB Fishing]

OK, if I put the splice directly onto the wires going to the bulb, which wire should I put it on, the brown or the black??

Thanks again!

Matt

 

[shizzy77]

are you pulling the power for the lights or power to the relay to switch the lights on? If you are just pulling a wire for the relay, any wire will be fine

I would not pull power right to the switch on any kind of lights. I would use a relay. As stated in the article, pulling the power directly through the switch can cause all types of bad things.

Power to the relay for the switch off one of the low beam wires. then nice large wire to the lights directly out of the fuse panel.

 

[Zum]

Couldn't you just give the fog lights their own independant switch?
You may not want them on with your low beams or is there a switch that you can control that with....probably is.Thats why I'm wondering why it needs to be the low beam power source,if you can turn them on or off,I'd probably just run it's own 12V wire.

 

[BYOB Fishing]

Yes, the fog lights have to have their own switch, and I am using a relay. The switch flips the relay, but I need a power source for the switch. The directions say that it is illegal to have the fog lights on when the low beams are not on. So that's why my question was if it's ok to splice into the headlight wire going to the bulb for this power, and which wire would I splice in to?

Thanks, Matt

 

[huntinfool]

I would "assume" that black is ground and since brown is the only other option that, that would be power. On a trailer the brown is the running light. But every vehicle is different.

 

[BYOB Fishing]

I used the brown one. Everything seems to be working just fine. I'm really impressed with the PIAA kit. The only fog lights I've ever hooked up are the Wal-Mart ones, and after seeing these, I would rather spend the $$ on a good kit. The wires from the relay to the battery were 10 gage, and the switch wires were 14 gage. And they had good automotive connectors, no spliced ends or anything.

Thanks for the help!

Matt