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joey4821 12-30-2012 06:03 PM

KC light install problem
So I just rigged up some KC 100watt 6" windshield mounted lights and they will not come on. The wiring is properly run (I checked it 10 times). However I noticed after I finished that the instructions say to take the fuses out before wiring up the lights then replace the two fuses just before hooking everything up to the battery. I had the fuses in the whole time I was installing and wiring them up. Could this be the reason they are not turning on? I can't figure it out. This is the link to the exact lights I purchased KC HiLiTES 100 Watt Daylighter Pair Pack System, Black 6" Round KCH-238

Does anyone have any suggestions? Very frustrated...

tallzdatank 12-30-2012 06:05 PM

are the fuses blown?

joey4821 12-30-2012 06:15 PM

No I've pulled the fuses out and they look fine.

B-wils-TJ 12-30-2012 06:18 PM

I had the same problem with my in line fuses. One of the didn't have a good connection. You could try wiggling the fuses with the switch on to see if that works

jp2611 12-30-2012 06:20 PM

Have a test light?
I would check at the plug/ junction where the lights plug in at the housing and ensure that I have hot AND ground at that point......if not trace back and see at what point it doesn't work.....

joey4821 12-30-2012 06:30 PM

na I don't do much electrical work so I never bought a test light.

MosesTJ 12-30-2012 07:49 PM

I would double check your ground if you do not have a tester. You can get one from advanced for a couple bucks.

Dextreme 12-30-2012 07:52 PM

A $5 multimeter from Harbor Freight is great for troubleshooting and tracing the problem....takes the guess work out. I had a KC light bulb go out a few days ago and I was able to measure that the two wires were getting 12v to the bulb, so I new the bulb was shot. :thumb:

Jerry Bransford 12-30-2012 08:02 PM

2 Attachment(s)
Put your ear next to the relay as someone flips the KC light switch on-off with your Jeep parked in a quiet location. Does the relay make a soft audible click as the KC switch is turned on & off?

Think of that relay as a remote control switch for the lights. The relay is what turns the lights on/off, with the cockpit switch what turns the relay on/off.

Telling us if that relay is energizing or not will help us to diagnose the problem.

Here are two good wiring diagrams that may help you to understand how it all works so you can figure out what is wrong. The "high current load" in the first animated schematic are the two driving lights, click on it to start its animation.

monkeee2002 12-30-2012 08:20 PM

get yourself a tester light. They're too cheap to not have one.
Check for power at the fuse - upstream & downstream of the fuse. Also, double check your ground wires (if both lights are failing to power up, then it's probably not the ground, but it never hurts to check). Try running a spare length of wire from the light's ground to the battery negative terminal, or a similar "guaranteed-good" ground location.

joey4821 12-30-2012 09:22 PM

So I just had someone turn the switch in my dash on and off while I listened by the relay and I heard nothing. . .

Looks like I'll make a trip down the street to harbor freight tomorrow for a multimeter, but in the mean time checking for the audible click was the only thing I could do tonight.

Wesboy 12-30-2012 09:52 PM

Have you wired them up so you need your headlights/high beam on for the KCs to work?

Motowithy 12-30-2012 10:48 PM

As above member said. I have the same lights and I know they tell you to piggyback off the headlights so it might be you wired properly and just have to put the headlights on and then try the switch.

jp2611 12-31-2012 05:59 AM

I am assuming here.....and this may or may not be correct.....and is not KC light related exactly.
You said you don't do much electrical..hence no test light. You are going to pick up a multimeter while inexpensive is more than a simple test light. Which also means it does more....but when it is not working COULD throw you off...also requires batteries in most that I have seen. If you are not real familiar with electrical a "iffy" multimeter could cause you problems while you try and diagnose an issue, say you pull it back out of the bottom of the tool box down the road and think everything is "fine" with it. And in reality it is not working due to poor batteries, or broken wires or something got loose came loose from rattling around in the bottom of the tool box.

A multimeter is great to have if you have the know how and are checking sensors for values/ and known needed values at certain times when certain conditions are met. If that is something you see your self doing than a multimeter is the way to go.

If it is mostly testing lights.....

My suggestion:

Get the mentioned test light.

Get a couple/ 4 small "alligator clips" than can be attached to the end of a piece of wire.

Get 2 small coils of red one black.

Make a couple about 6 foot jumpers. Save the extra wire for "just in case" some day you will need it.

The test light is very basic and if there is ever a can use the jumpers from the battery to test any light issue and 6 foot will just about reach it anywhere on the Jeep.

Total cost will be about $10 but if all you are ever going to do is lights, you will be pretty well set. ('cept for wire-pliers/ cutters and some end terminal connectors)

Steve305 12-31-2012 07:52 AM


Originally Posted by Wesboy (Post 3162192)
Have you wired them up so you need your headlights/high beam on for the KCs to work?

THIS ^^^^^ question needs to be answered. ;)

joey4821 12-31-2012 09:53 AM

No I have not wired them to be turned on with my headlights. they are wired separately. They are wired almost exactly like the second image Jerry posted.

this is the image given to me with the instructions.

Jerry Bransford 12-31-2012 11:11 AM

Your relay isn't clicking (energizing), at least you can't hear it clicking. The relay is a very basic circuit, it's not as difficult as some think it is... so it's not hard to get working if you take some very basic steps.

There are four main connections on a relay when used for driving lights... two of those energize it, the other two are simply the on-off contacts that turn something on... like your driving lights.

Pins 85 and 86 on the relay are the two leads that when power is applied to them, energize the relay. If those two pins get 12v, the relay will energize. All those two connectors need to energize the relay is a ground and +12v. It doesn't matter which of those two gets ground or the +12, they are not polarity sensitive. If you connect a ground to one of them and +12 to the other, the relay will energize.

Find out which is missing on those two pins, ground or +12v, and you'll find out why the relay is not turning on. Incidentally, those PIN numbers like 85 and 86 are molded onto the bottom of the relay next to connections themselves. Pins 30 and 87 are the on-off connections for the lights. :)

joey4821 01-02-2013 04:53 PM

I want to thank everyone for all the help. I just got off the phone with the guy from customer support at KC lights and he told me to take the ground wire and put it on the negative side of the battery. And now it works. . . Go figure. Now off to try them out and aim them.

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