Okay...I probably deserve some crap and grief from this because I went SOOOO cheap. I had been putting off trail lights for over a year and with my upcoming wedding, trail lights looked to be over a year out SO I was at Harbor Freight and saw on clearance some 100 W halogen trail lights for $20! I couldn't resist....even for $20 if there are just there for the look it is worth it.

But I tried to install them. They are a standard 12v lighting system with a simple positive and negative wire into the lamp. So I used a wire tap from Home Depot and tapped from the lamp positive to the white (with color stripe) positive wire from the stock fog wiring. I am running a Shrockworks stubby bumper that had no fog lights in the bumper and so my stock fog wiring was just sitting there unused. I did the same for the negative from the lamp and wire tapped it to the stock black ground wire. Then I went to turn on the fog lights from the cab expecting to see more lights like a christmas lighting display from Clark Griswald....but to my surprise there was a single flash of light and then dead. At first I thought I shorted something, but then the light came on again for a flash a couple seconds later (30 or so) and then again. The flashing continued at seemingly the same interval probably for 4-5 times and then it was dark until I would turn the jeep off and back on, then I could get the behavior to repeat.

I then tried to take my stock bumper lying in my garage and hook up the fog to see if there was a problem with the new cheap lights, or it was the Jeep wiring/ circuits controlling this flashing behavior. Behold the stock fogs acted the same way (now at this time I had wire tapped both new lamps). I am certainly no electrical guru....and I know nothing about jeep lighting (especially fog) wiring. I just thought...take 12 v light and hook up positive to positive and negative to negative and it would be bright as the 4th of July....any ideas or help please?

 

Hope you didn't fry anything there.

Disconnect those off-road light wires pronto...

The on again off again is either the Jeep's computer or a resettable breaker.. but I am too lazy to look it up for you right now... either way you get the jist.

Run your power straight from the the battery, and through a fuse and a switch! Run ground to a good ground spot close to the lights, or some like to switch ground but I am not sure of the reason for this. But that is an option also.

EDIT... If you want to check your lights you can just ground them to the jeep and touch the positive wire to the positive battery terminal to make sure they are working correctly.

 

okay...I get it, might have fried something.....disconnect right away.

OKay, but that still doesn't answer what is going on. Does the jeep have an overload preventer that is cutting the power making it flash?

 

Not positive, but I believe it is an automatic reset breaker, so it trips, times out, and then resets, then (if the load is still to high) trips again.
Thats my best thought without doing my homework.

 

so I don't get it...why would the stock wiring for the fogs not be able to handle a typical 12v off road light kit?

 

The issue should be the breaker tripping and reseting. The standard fog lights are only 55 watts. 100W is just shy of twice the current draw. The jeeps thinks the wiring it shorted out. If you want to use the stock fog light switch you need to use it to trigger a relay. Get the power for the relay, fused and straight from the battery.

 

Oh excellent...thanks for the feedback, yes I would like to stick with the stock fog switch as it is very clean and I dont have the stock fogs with my bumper. So it sounds like I need to replace my stock relay and add a bigger fuse in the fuse box? Is that correct? What size fuse do I need to provide to adequately protect my electrical system and stock wiring?

 

actually I would get a relay kit and make the trigger wire for the relay the fog light positive. this way you are pulling power from the battery, they only come on wit the stock fogs, and your not overloading the circuit.

Now you may want to be careful with this and check your local laws, because most places will only alllow one set of fogs to be on while driving, unless off road.