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Has anyone hooked up some high powered lights to the factory fog lamp wiring? I have some old Dick Cepek's that I tried out (150watt)and I guess they popped the factory fuse pretty quick (kind of expected that). Is putting in a 40 amp fuse a bad idea? Thanks :lol:

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http://community.webshots.com/user/drifterdave
 

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Dave:

The factory fog lamp wiring is relatively light, (no pun intended), certainly not any larger than 16 awg, so putting a 40 amp fuse in is not a good idea. I'd recommend new wiring and a new relay for those manly lights.

Jerry
 

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cheep fix

leave stock lights on replace factory bulb (24 watts) with (100 watt) bulb

less then $10 mod...note: to remove the bulb inside the lamp you have to disconnect the wire don't pull the bulb

then find the relay for the High beam/fog lamp disconnect...(under the hood) this relay prevents both high beam and fog lights for going on at the same time...carefully pullblack plastic cover off on relay and stick a piece of plastic in to prevent the relay from tripping

now you have ability to have both high beam and 100 watt fog lamps on with no rewiring etc... works fine for me no problem so far...

if you burn the bulb out put your 24 watt back in..

good luck
 

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I agree

This light mod and bulb change are easy and effective. Should be the first thing a new owner does.
 

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No problems with the factory light housing warping or melting with the 100w?

But very cool though.
 

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Nope

Not yet at least, just stay out of the high water if they've been on awhile.
I used the Sylvania H3 100W, had to nip off the little nub then drop in like normal. I also replaced the stock HL's with Sylvania XV's. They're as good as the Silverstars I have in my Liberty and only a third of the price.
 

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Just looked up the wiring diagram in the FSM and the fused wire to the relay connection and then to the lamps is a single 16 AWG. For the stock factory bulbs (24W x 2), there will be approximately 4 Amps of current running through the wire. If two 100W bulbs are used as replacements, the current running through the single wire will be approximately 16 and 2/3 Amps. The maximum current a 16 gage wire can safely handle at room temperature is 10 Amps . So, there is a strong possibility as the wire/insulation ages, or gets heated, the insulation will start to melt and short that circuit out.

I would either run a parallel 14 AWG wire between the fuse and relay and then to the lamps, or run a whole new wire. FYI, 12 AWG can safely handle 20 Amps and 10 AWG can handle 30 Amps. Normally a safety margin of 25% to 50% is used to ensure reliability.

These ratings are given at room temperature and as the ambient around the wire increases, the current rating will decrease due to an increase the the wires resistance.

Have a great day!

Ken
 

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and bubble bees can't fly

I hear you, but not an issue. You could use the PIA 55W bulbs if you're concerned.
 

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That's a good point. 50W bulbs will only draw around 8.3A so I think I will be going with 50 watters.
 

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Cool Info
 

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Re: and bubble bees can't fly

PJ said:
I hear you, but not an issue. You could use the PIA 55W bulbs if you're concerned.
It probably won't matter considering how much I use my fogs but on the other hand, I wouldn't want my Rubi to do a Caravan impression.
 

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I think there is probably enough margin to safely use two 55W bulbs since the lights are normally on at night when the ambient temperatures are down and the vehicle is normally moving so heat is pulled away from the insulation surface. Good luck and have a great day!

Ken
 

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Ken White said:
I think there is probably enough margin to safely use two 55W bulbs since the lights are normally on at night when the ambient temperatures are down and the vehicle is normally moving so heat is pulled away from the insulation surface. Good luck and have a great day!

Ken
Thanks Ken.
good info for those who want a little more light.
however in my area of the "dry heat basin" night temps still run into the
higher 80`s or 90`s... so best for me is new lights..keep the factory ones
intact.
mac
 

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Mac, with 55W PIA's, you would definately be pushing the rated current limits. However, it has been my experience that the UL ratings for the wires are fairly conservative - they have some built in margin already to account for aging and some mis-application. Have a great day!

Ken
 

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Also if you keep your original fuse, should that not keep it from "going to far" /Meltdown/?
 

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The original fuse is rated at 20A - which implies the wire may be of a higher grade than the UL version of 16 AWG I quoted.

The purpose of the fuse is to protect all of the circuits/links between the battery and the fuse block should an excessive current condition occur on the load side: wiring, relay fog lamps. So, the wires could melt on the load side, or any other abnormal condition could occur, and the fuse will open once the rating is exceeded. The rest of the electrical system will stay intact as long as the fuse is of the same size or smaller. If a larger fuse were used in the 20A socket, then yes you could theoretically cause a major melt down if an increase in current condition occured that was less than the fuse rating but greater than the wire rating - this means an electrical fire. A direct short would probably blow the fuse and protect the wiring for either fuse.

I would guess the 55W PIA's are safe, however, I would not recommend using 100W replacements without a wiring upgrade.

Just my opinion. Have a great day!

Ken
 
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This is a good thread. I've been wondering myself what I can get away with using the existing wiring. I'm getting the ARB bull bar and I was planning on using the existing wiring for smaller Hella fogs (hopefully they'll just slip through the turn signal openings on the new bumber. These new fogs use 55W H3 bulbs so I'm still debating on whether this would be worth it.

It's actually pretty funny that I'd buy the Rubicon, which is over-kill in most situations, but then even consider skimping on wiring that could just as easily leave me stranded :roll: .
 
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I am surpised to find that running a couple additional wires to have the desired lamp wattage is intimidating to this group of stalwarts who generally think nothing of replacing the suspension in its entirety!
 

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I am running a set of PIAA 520s off of the stock wiring and have had no problems at all.

 

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RubiDan said:
I am surpised to find that running a couple additional wires to have the desired lamp wattage is intimidating to this group of stalwarts who generally think nothing of replacing the suspension in its entirety!
thats funnnnny

i am going to run new lights and wires.
just takes time.
:wink:
 
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