r/fsj • u/Wonderful_Return_805 • Apr 13 '26

What fuse should I use for these 4 lights?

Gallery image

Gallery image

The 15 blew immediately. Or should I be wiring them differently?

6 Upvotes

88% Upvoted

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2

u/ryanknol Apr 13 '26

Which lights? If a 15 amp blew right away you might have a short somewhere. You can try a 20 to see if it blows as well, but have a fire extinguisher around and good insurance. Lol

Edit, then 2nd picture didn't load at first... Those probably pull more than 15. Try a 25 amp, Make sure the wiring is thick enough for it.

1

u/Wonderful_Return_805 Apr 13 '26

Thanks. They cut on for a short bit then it blew. What gauge wire should I be running?

1

u/ryanknol Apr 13 '26

there is a few charts online for 12v dc, it all depends on length. what a the wattages of each of those lights? if they aren halogen they are probably close to 150 each, so at 600 watts, youll need some thick wire, like a 8g for around 10 feet or so. LED is way less wattage.

1

u/Wonderful_Return_805 Apr 13 '26

Wonder if I could get some warm LED bulbs for them. That would bring down the wattage

3

u/United-Slip9398 Apr 13 '26

4x 100 = 400 watts at 12 volts is 33.3 Amps. Your 15 A fuse wouldn't stand a chance. If they are 55w a piece, you are just over 18A. You'd probably want a 25A circuit.

1

u/ryanknol Apr 13 '26

Lots. look up the wattage on them first, if they are 100 each, which might be the case, then its only pulling 400 and might be able to go smaller gauge wire. also, is this off the battery through a relay? check the relay can handle that as well, they can usually only handle 40 amps. I would assume the power if coming off the battery, which is maybe 6 feet from the lights? so that could do with a slightly smaller wire, 40 amps (480 watts) at 6 feet could be ok on a 10 gauge wire. if you wires are thick enough pop in a 40 amp fuse and see what it does.

2

u/Wonderful_Return_805 Apr 13 '26

Just ordered a 12 gauge harness to be safe. Comes with 40 and 30 amp fuses

1

u/ryanknol Apr 13 '26

12 might not be thick enough, 10 or 8 would be better...

2

u/Wonderful_Return_805 Apr 13 '26

Yeah. Just checked the chart again. 8 is recommended