Fog lights problem


  #1  
Old 12-02-18, 01:26 PM
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Fog lights problem

Finally went to install fog lights on my RAM. They don't work.
It's standard set up. 2 fog lights with harness. Harness has relay and fuse. Switch for the inside. 3 black wires, one for relay, one for switch, one for fuse.
Had everything connected, lights don't work. All black clips were directly on battery negative.
Relay clicks.
Switch has power to it and appears to be working ok.
There is no power to fuse and no power to the light. Fuse is past relay.
Relay plug has 12V to it. Relay is removable. I checked.
I contacted seller a moment ago.
Question is - it's bad relay, right?
Do I even need it? Can I simply wire this direct, via switch and fuse?
I had to cut OEM bumper bezels for fog lights, to make them fit, so I am sort of stuck with those lights. I mean - I cna return them, or exchange - and drive with big holes in bezels.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
 
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Old 12-02-18, 02:51 PM
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I took close look at that harness..
What exactly is fuse supposed to do, if it is not inline with lights/relay?
Switch has 3 wires going into harness clip. Red, white and black. There is black wire coming out of clip, to negative.
Relay box has black and white out to the fog lights.
Same relay box has white wire going to fuse box - and then fuse box has negative black coming out to negative somewhere on a car. How is that fuse supposed to do anything, if it is not inline with either switch wires or fog light wires?
 
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Old 12-02-18, 04:11 PM
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would look at the relay see if it has pin numbers standard 5 pin relay numbers is 85 and 86 for the coil and 30 and 87 or 87a for the switch most often 87a isn't used as its the normally closed position with the relay off but if they was using the switch to supply power they could be using it as a high beam cut out relay perhaps and be using 87a.

I would assume that wire colors mean nothing if they have a black wire going to fuse certainly shouldn't be ground.
 
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Old 12-03-18, 12:39 PM
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It's 4 pin relay.
I'll take picture of harness tonight, seller wants it anyway for exchange. The picture, I mean.
Alan, everything you said is Chinese for me. I am not that savvy electrical wise - but thank you.

My question is - do I really need relay, or I can hardwire it through the switch, bypass relay completely, and call it a day? I have to drive in complete darkness on half mile serpentine with VERY tight turns. Fog lights illumination would have helped a lot.

Lights are LED, I do NOT see them draw huge current. That's what relay is for, right? To prevent overload. It's LED, what overload....
 
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Old 12-03-18, 01:32 PM
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most led lamps dont draw much current so you are correct that you probably do not need a relay however a relay allows them to use a much lower amp rated switch and smaller gauge wiring to the switch.
 
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Old 12-03-18, 02:28 PM
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"a relay allows them to use a much lower amp rated switch and smaller gauge wiring to the switch"

Right; that's what it ultimately boils down to. If you were to, for example, run a wire from the battery through a fuse to the switch, then to the lights, then to ground, and if your fuse, switch, and wires are properly sized, everything will work just fine. If however, for example, you were to use a factory installed switch, whether the headlight switch or accessory switch, it most likely is not sized for that kind of load, in which case a relay would be necessary.
 
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Old 12-03-18, 02:37 PM
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Also, figures I have 3 wires to the switch and 2 wires to the lights.
I'll post pic later. That fuse wire does not make any sense at all the way it is... just a pigtail with fuse box...
That said, I could simply take a 20 amp rocker switch and plug it in, right? To keep it simple. Of course, sucks I paid for harness, but I need close to bumper lighting and don't want to go through return/wait on new lights to come in - maybe no better.
 
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Old 12-03-18, 02:46 PM
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Hmmm.. what year ram? My truck had all factory wiring there already. just get the factory lights, they pull a factory switch from the junkyard off a tahoe or an optioned silverado and just plug in at floorboard box..

Just like I did with my brake controller.

In fact I added another horn that wasnt there. Plug was there, I just added the horn..

But take pics.

Trust me , use the relay. I tried to do that with a 79 montecarlo with no relay and caught the car on fire under the dash.. I was 17 years old and stupid back then..
 
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Old 12-03-18, 03:42 PM
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2005. No harness. No wiring. yes, I know, they usually have one harness per vehicle and simply tape unused plugs. Not mine. Also, it's a rebuild, bumper was replaced, so who knows.
 
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Old 12-03-18, 06:47 PM
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Ok, here's harness pics.
File too big to upload.
Look at the fuse box. What? How is it even supposed to work?
I figure, basically, I can splice fuse directly into black wire to lights and connect 3 switch wires to high load On/Off switch.

https://drive.google.com/open?id=1G_...nLm1M7q45mdfxT

https://drive.google.com/open?id=1Hh...nJgT7IcO_XLtRi

Red wire from switch is power positive lead.
 
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Old 12-04-18, 02:07 AM
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looks to me like the fuse wire should go to battery positive or positive junction block it is a white inside a black wire loom, the black wire coming from the switch and the relay do appear to be ground the red wire to the switch should be positive also but I think I would hook into your low beam headlamps so fog lights only operate when the low beams are on, so you do not blind oncoming traffic, it is a lighted switch so it should only light up when your lights are on at night you could hook it to park lamp circuit and have it work on both low and high beam.
 
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Old 12-04-18, 08:46 AM
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Yes, I had all black clips connected to battery negative direct. Red was connected to battery positive.
As I said, switch light is on.
There is no 12V to fuse and no 12V to lights. Basically, past relay - no power.
Relay clicks when switch is operated.
Please, go easy with obvious to you electrical stuff. I need "guide me by hand" step by step with this. Last resort I see, I can splice fog lights into headlight wires. So fogs are on every time I turn headlights on. U RARELY use high beams.
Of course, then I basically paid for useless harness.
 
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Old 12-04-18, 11:31 AM
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the fuse wire should go to battery positive this is what supplies power to the fog lamps.
the red wire coming from the switch only energizes the relay coil it does not provide power to the lights.
the red wire that energizes the relay coils only pull a few milliamps but this still needs to be on a fused circuit that is already in the vehicle by splicing into your existing wiring like the tail lamp circuit. they also make fuse taps that allow you to easily install the red wire at the fuse box without actually splicing into your existing wiring this is how accessories are usually installed.
https://www.amazon.com/Qiorange-circ...=fuse+mini+tap
 
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Old 12-04-18, 01:37 PM
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the fuse wire should go to battery positive this is what supplies power to the fog lamps.

wdf is it black then? Are you sure it has to go to positive? I OBVIOUSLY had it connected to negative, based on wire color...... Maybe that's the solution to whole problem. Seller is no help.
 
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Old 12-04-18, 01:42 PM
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So the red wire from switch does not go to battery? Wish they sent me any relevant instructions... Anyhow, is there any EASY to get to wire under the hood that I can tap it to? Tap box was actually included with kit.
EASY to find. I rather not dive into the depths of what is where in the fuse box.
Btw, not to be a pig. thank you, Alan
 
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Old 12-04-18, 02:08 PM
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would look at your front park lamps see if one of them is easy to get to some vehicles the fuse box may be easier method as the lights are buried, but if you have easy access to a park lamp then I would try there, your tail or park lamp fuse is likely inside the cab fuse box.
 
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Old 12-04-18, 03:33 PM
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Yes, my headlight assey is very easy to get to.

Alan, last question. Black wire from the fuse for sure goes to the 12V positive?
 
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Old 12-05-18, 01:49 AM
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yes and according to your pictures its not black, both wires coming out of the fuse holder are white but they are in a protective sleeve that is black like most of the wiring harness. if you just want to test it real quick move both the red and the fuse holder wire to battery positive and turn them on.
once you hook up the red wire to the park lamps the fog lights wont come on unless the lights are on and most all vehicles now have auto driving lights anyway, but if for some reason you was trying to turn them on without the lights on then the relay would never turn on.
 
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Old 12-05-18, 08:28 AM
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You are right. I saw black sheath on that wire and presumed it's black, = negative. Well, guess this is the solution to the problem. I'll toss harness onto the battery tonight, and check with multimeter if there is power supply to light leads. Too much trouble to crawl underneath the truck and connect dem leads to lights.
Any harm with connecting red from switch directly to battery? I drive truck daily, it's not gonna drain it.
 
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Old 12-05-18, 01:27 PM
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it needs to be fuse protected you could just tap into the other white wire of the fuse holder so if it does ever short to ground it would just blow the fuse instead of possibly causing a fire. it could be a drain on the battery if the switch is illuminated all the time, but it may only light up when its in the on position or maybe both but not enough to probably drain the battery in a day.
just because you are driving it every day now there may be some time in the future you will not be so I wouldnt leave it hooked there without unhooking the switch ground wire to eliminate the drain on the battery.
 
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Old 12-06-18, 09:23 AM
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I am not worried about fuse wire. That goes onto battery plus.
I am simply no good with any beyond basic skill level electrical stuff. Tapping into fuse boxes etc makes me feel uneasy.
Red switch wire is about just right length to reach to the battery positive and then have a foot of slack, with switch glued to the dash.
If I were to tap it to a headlight wire, what I can do easily, as I have LEDs installed, so wires are exposed, I'll have to lengthen switch red wire to make it happen. No big deal, I can do this. Will this be a basic simple connection?
Otherwise, I have always hot 12V outlet inside the cabin with charger plugged into it and staying always on. Even when I drove truck twice a week, I never had any drain issues with that. I can't possibly imagine switch drawing any more power than always on charger. Does it make sense?
 
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Old 12-08-18, 01:25 PM
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Working fine. Thank you, Alan.
It was the fuse wire, that was hidden inside the black sheathing that confused everything. Of course, complete lack of any relevant install instructions with the lights too.
Now I have different problem. they are way bright.
 
 

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