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Discussion Starter · #1 ·
Okay i hooked up offroad lights on a roll bar for my truck, all legit had no issues with wiring everything worked for weeks since i've had it. Put a stronger fuse the right fuse in and i was all done. Today i went to turn them on, nothing, figured dead fuse. Open the hood, sure enough dead fuse, pull it out and go and stick a new on in and i get sparks coming from it. Why is this getting power all the time? my switches are hooked up by the ground. Heres my wiring diagram.

rollbar.jpg



ps: Trailer plug is for a quick disconnect if i ever need to pull the roll bar out for a bigger load. Its the kind with 4 wires, two are hooked to power the other two separate grounds.
 

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You’re going to get some sparking when you put in the new fuse because you’re bridging the gap between the two ends of the power cable (hope that makes sense).
Does your fuse blow immediately or just when you turn on the switch?
Either way you’re pulling too much current which means you have a short that is pulling your power to ground. If it were me I would get my multimeter (DMM) and ohm out the power cable to find the short.
Hope this helps in some way
 
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:word: I'd guess that you have a short. What's the rating on the fuses you've been blowing? Generally speaking, it's a really bad idea to replace a fuse with a higher rated one after it blows. Good way to start a fire.

Another thing to consider...you really should wire those lights up with relays. You don't want ALL that current flowing through those switches in your cab. Again, another way to start a fire :D
 

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I gather the fittings are plastic and the neg's from the globes aren't grounded to the mounting bolts?
Not used to seeing the neg switched. Typically switch the pos wire. Also...relays are a 'must'.
 

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Discussion Starter · #5 ·
as soon as i touch it with a fuse it sparks, if i try and put it in in blows, it does this with a ten amp fuse and a 30 amp fuse. And yes i know replacing one with a bigger one isnt a good idea but i had only a ten amp with me and just wanted to see if they would work at all, i was told 30-40 amp fuse would be best after. and i checked the dc with my multimeter and its pulling 12.?? and i checked the back where the bulbs are bolted to the bar and pulled some of the wires out and re taped them and checked each one but each time it blew a fuse
 
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If you're blowing fuses while the lights are switched off, you have a short somewhere. Read up on wiring in relays and redo your wiring.
 

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Can you take a pic of one of the fittings and how it's wired and mounted?
Have you checked the trailer plug to see if there might be water/moisture in there?
 

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Discussion Starter · #8 ·
yeah i am going to check it this weekend, we just had a big storm and im assuming something got wet there, if not im probably gunna re-wire the bar and recheck it, if everything is fine leave it as is, if it still pops im guessin its part two to my wiring haha
 

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Try narrowing it down.
Unplug all 4 lights and then put the fuse in. Turn the switches ON.
If the fuse holds....start plugging the lights back in one at a time.
Should be very easy to find. That's a very (albeit backwards) circuit.
 

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Discussion Starter · #10 ·
yeah thats actually a smarter way to do i haha thanks!
 
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