KC halogen HiLites troubleshooting

jrmcafee

jrmcafee

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Hey gang, 65th Anniversary Ed. with a set of 3 bumper-mounted halogen KC HiLites the PO added. I've had the Jeep a little over a year and they haven't ever worked.

It's bothered me for long enough now I'm trying to figure it out. So, here's what I've done so far:
  • Checked the bulbs--all filaments appear intact
  • Checked bay and interior fuses--all good
  • Tried all lighting combinations--lights off, markers only, low beams, low beams + factory fogs, high beams
  • Checked the connector between the light assembly and the pigtail into the engine bay--looks good, no corrosion
  • Checked the wiring at the bay fuse box
    • Grounded to bay (black)
    • Yellow/White running into relay, Red/White running out of relay
    • Red also has in-line 15A fuse and is wired to battery and fuse box terminal--15A in-line fuse was blown but replaced and still nothing
  • Followed wiring through firewall
    • Wired cleanly into rocker switch in factory auxiliary gang near cigarette lighters
  • Pulled out center stack dash bezel to check rocker switch terminals--still clean and shiny, clip firmly attached
  • Went through with a voltmeter--everything seems to be putting out the right power
So I'm stumped. About the only thing I can guess is that even though the rocker switch is similar to factory and appears in good condition, it's clearly aftermarket and not from KC (theirs appears to usually be a generic rocker with an LED that's provided with a custom mount). My paranoia has me wondering if perhaps that rocker can't handle the circuit even though it appears to be in good shape.

I can add pictures if that's helpful but based on the YT videos I've watched, it seems to be a pretty standard setup. Ideas? Thanks for your help.
 
So the switch doesn’t handle the load, it just tells the relay to connect, the circuit to the lights is really battery to relay to lights.

You’re getting 12v at the light? You’re sure? Does it switch in and off with the rocker?

If yes, then what about the ground, are you sure it’s grounded well?
 
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LONGJP2 said:
Check for power at the relay. Usually pin 30
If good, then jumper across the relay. Usually to pin 87.
Lights should come on.
YRMV
Click to expand...

This too, you’re basically taking the switch out of the equation. If that doesn’t work, focus from batter to really to lights, I had a dead KC in the bumper and the ground was the killer
 
I just went through this. I bought some wire and did some direct wiring to check the bulbs. Then did just the pos, then the ground, isolate one at a time, a ConnectIQ done years ago by PO was corroded in the dad gum ground in a wire loom, annoying.
BC0414E0-DDAA-4089-AFF1-1208384A6407.jpeg
 
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If the lights are grounded to the bumper/frame, that may (or may not) be the problem.
I've heard the frame is not a good ground source. 🤫
 
Best advice for troubleshooting electrical is to buy a multimeter. Everything is just speculation unless you can check voltage.
Harbor freight has some cheap little guys for around $7.
 
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jrmcafee said:
Hey gang, 65th Anniversary Ed. with a set of 3 bumper-mounted halogen KC HiLites the PO added. I've had the Jeep a little over a year and they haven't ever worked.

It's bothered me for long enough now I'm trying to figure it out. So, here's what I've done so far:
  • Checked the bulbs--all filaments appear intact
  • Checked bay and interior fuses--all good
  • Tried all lighting combinations--lights off, markers only, low beams, low beams + factory fogs, high beams
  • Checked the connector between the light assembly and the pigtail into the engine bay--looks good, no corrosion
  • Checked the wiring at the bay fuse box
    • Grounded to bay (black)
    • Yellow/White running into relay, Red/White running out of relay
    • Red also has in-line 15A fuse and is wired to battery and fuse box terminal--15A in-line fuse was blown but replaced and still nothing
  • Followed wiring through firewall
    • Wired cleanly into rocker switch in factory auxiliary gang near cigarette lighters
  • Pulled out center stack dash bezel to check rocker switch terminals--still clean and shiny, clip firmly attached
  • Went through with a voltmeter--everything seems to be putting out the right power
So I'm stumped. About the only thing I can guess is that even though the rocker switch is similar to factory and appears in good condition, it's clearly aftermarket and not from KC (theirs appears to usually be a generic rocker with an LED that's provided with a custom mount). My paranoia has me wondering if perhaps that rocker can't handle the circuit even though it appears to be in good shape.

I can add pictures if that's helpful but based on the YT videos I've watched, it seems to be a pretty standard setup. Ideas? Thanks for your help.
Click to expand...

What it looks like is the kc lights are wired in pairs with the kc harness and relay. If so you know the relay and switch is working as you have one of the lights on. Check for power at the plug going to the inop light. Do you have 12 volts? Now check between the pos and neg pins at the connector. Do you have 12v?
 
Had the same problem a few years ago. After chasing down every other possibility, it turned out it was simply a bad ground.
 
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This afternoon I replaced the dash switch with a new one from Amazon. The amber indicator that was not working on the old switch is now working with the new one, so I know I'm getting power to the switch.

Best I can tell from looking at pictures of other KC setups, my relay has been rigged a bit. It's a 30a 12v relay but it's a 4-pin instead of 5 and I have some wires that don't match up. That's my next culprit to eliminate.

I'll also take a look at the ground but from what I have seen thus far, the ground has been placed in a really good spot. Can always move it to the neg terminal though.
 
You need to be sure the relay works and is wired properly. You can also hear them click normally.

And yes, you need to verify the lights work by a straight jump- a large percentage of residential electrical service calls are simply burned out bulbs.
 
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I would not buy more anything, except a test light.

Test the connections to find out what’s getting power.
I agree with ^^^
Run a jumper straight to the positive on the light, it lights up, then bulb is good.
Then take the main wire going from Relay to lights, and jump power there. Then you know. Then look at a relay wiring, and jump to that, and it should light up.

If it’s a jacked up relay, maybe go ahead and get the one they have then every auto parts store, and do a good install.

I would just assume they wouldn’t install them and they never work, so that relay must have worked for this.
 
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Harbor freight sells small voltage meters for less than $10. Troubleshooting electrical without a meter is not easy.
 
cpwolf said:
I would not buy more anything, except a test light.

Test the connections to find out what’s getting power.
I agree with ^^^
Run a jumper straight to the positive on the light, it lights up, then bulb is good.
Then take the main wire going from Relay to lights, and jump power there. Then you know. Then look at a relay wiring, and jump to that, and it should light up.

If it’s a jacked up relay, maybe go ahead and get the one they have then every auto parts store, and do a good install.

I would just assume they wouldn’t install them and they never work, so that relay must have worked for this.
Click to expand...

+1 on the test light, super easy to see if you are even getting power to the lights.
 
cpwolf said:
I would not buy more anything, except a test light.
Click to expand...

Gollywomper said:
Harbor freight sells small voltage meters for less than $10. Troubleshooting electrical without a meter is not easy.
Click to expand...

jeepguy03 said:
+1 on the test light, super easy to see if you are even getting power to the lights.
Click to expand...
A cheap multimeter will not only let you test for voltage, but help you find broken wires by letting you test for continuity. A light is good, both is better. If the light shows no voltage, the meter can help you find out why.
 
C.J. Roberts said:
A cheap multimeter will not only let you test for voltage, but help you find broken wires by letting you test for continuity. A light is good, both is better. If the light shows no voltage, the meter can help you find out why.
Click to expand...

Agree, I have both, just the light is easier to crank out the testing ha
 
jrmcafee said:
This afternoon I replaced the dash switch with a new one from Amazon. The amber indicator that was not working on the old switch is now working with the new one, so I know I'm getting power to the switch.

Best I can tell from looking at pictures of other KC setups, my relay has been rigged a bit. It's a 30a 12v relay but it's a 4-pin instead of 5 and I have some wires that don't match up. That's my next culprit to eliminate.

I'll also take a look at the ground but from what I have seen thus far, the ground has been placed in a really good spot. Can always move it to the neg terminal though.
Click to expand...

The best way to test this is with a test light or voltmeter. Save yourself some grief and pick one up. I you go to harbor freight my suggestion is do not pick up the cheapest (they are junk) pick up the model above about $5 (they are less junk). When you have that test the test light to verify it works.
He next step is splitting the circuit down into sections to isolate the problem . I would start at the lights (easiest to get to) check for power with switch on. Check both terminals if you have power at one terminal grab a small pin or nail and put on the ground clip of the test light and use the test light in both pins of the plug if it lights you have a bulb problem. If it doesn’t light you have a ground issue. If you have a factory KC harness follow it back the ground wire will come out of the harness either at the relay area or between the lights and the relay.check this connection.
If you need to check the relay here is how if it is a standard Bosch type relay ( 1” square relay with 4 or 5 terminals) note pin 30 orientation to identify relay pins.
When both power and ground are applied to pins 85 & 86 the relay will close and connect pins 30 and 87. If power or ground is removed from 85 or 86 the relay will open and disconnect pin 30 from 87.
Remove the relay and check pin 30 and 87 for power. If you have power at on jump from pin 87 to 30 with a wire. The lights should come on.
If the lights come on check the control circuit 85 & 86. One of those pins should have power when the switch turns on if one has power check the ground circuit to the other terminal. If no power check the switch and wire to the switch. If it is a factory KC harness it sounds like a ground wire may have gotten disconnected.

534860E8-3517-45F5-AA9E-B1BCD6BD953D.jpeg
 
As it turns out, the relay was a 4 pin 40a standard auto relay, which is fine, but the hot line had bypassed the relay on an inline fuse direct to the switch. Running that line into the relay got my outer lamps firing. I still don’t have light in the center lamp. That’s next.
 
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