A couple of different things could be causing that fuse to blow---But first what amp fuse (((AND)) what gauge wire are you running?

Possible causes: too much draw from a shorted light. Too small a fuse for the application (BE CAREFUL...You NEED the proper wires to go up fuse sizes safely!!!!!!!!!!!!!!!!!!!!). Crap fuses..... but those are the usual culprits.

 

I am not sure on the Gauge of the wire only because I am using exactly what came with the KC Lights. I haven't added any wire. The fuse is a 3A, (again, what came with the lights)... The weird thing is that they have worked for about 3 months now, and then just suddenly stopped.

When Fay went thru, and a TON of rain - thats when they stopped... could water damage maybe hurt the fuse holder? I really don't know, it just doesn't seem right. I looked at all of the wiring to the switch this morning and it seemed fine... so I really don't know...

 

If you were to install a new fuse and it blew immediately, then I'd remove the fuse and start using the ohmmeter part of your VOM to determine where the wiring is shorted. Do this by disconnecting different sections of wiring, normally starting in the middle, then working in the direction of the short, halfway each time. If the new fuse doesn't blow immediately, or if you just prefer, you can also do a VERY thorough visual inspection of all of the wiring after the fuse (on the other side of the power/battery from the fuse). You're looking to see if any wire may have its insulation damaged. Be certain to open up the housings for the lights and see if there might be something amiss inside. Bare wire, burned/overheated insulation, water where water doesn't belong are all suspect. Clean up anything you find and you should be good to go. Just be sure to check every inch of wire between the fuse and the lights. Check the light bulb sockets, too.

 

Quick question about that...

Because there are two fuses - one thats 3A for the switch, and then one thats I think 25A for the lights... and the 3A is the one that blows - would that automatically tell me that there's no shorts on the Lights end? I did a really detailed inspection on all of the wires yesterday (just not inside the light housing yet) and didn't find any issues noticeable to the eye.

Could it be the ground of the switch not good enough? Would that cause it to blow?

 

Dam good question & unfortunately I dont have an answer for you on that one So free bump for someone who might......

 

Yes, that is a possible culprit; as well as the switch itself having gone bad.

 

Well what is weird to me is that when I replace that fuse, the switch does still work... so its not that going bad... so only guess left could be the ground I guess? Its working now that I changed the fuse (again) but theres nothing to say when it will cut out... Thanks for all the help, if I figure out an end to this problem, I will be sure to share it with everyone Thanks for the help everyone!!

DKJeep17

 

Sorry, I must have missed this the other day. Yes, it sounds like your problem is on the relay coil side, not in the lights circuit. However, if your system is wired up like mine, remember that the switch just applies a ground to the "far side" (from the fuse and battery) of the coil. That means if there's a short to ground in the wiring to that switch, or maybe even in the switch, the fuse won't blow. Rather, the fog lights will turn on when you don't want them on. I'd inspect the wiring from the 3A fuse to the relay--that sounds like where the problem is. You may also have some type of construction defect within the relay, causing the fuse to blow.

If you don't find anything and the fuse continues to blow, try removing the relay (is it socket-mounted?). If the fuse still blows, then the problem has to be somewhere between the fuse and where the wires attach to the relay socket. If the fuse blows, then the relay looks highly suspect--change it.

I hope this proves helpful.