Fog Lights not working

I have a 01 Limited that came with the factory fogs but one wasn't working. So I bought some aftermarket ones and I think that I hooked them up wrong. There are the 2 wires going to each fog light so I took the new ones and spliced into the factory wires. Instead of grounding the negative from the light I put it into the factory black wire. I thought that it grounded somewhere within the factory wiring since both wires went into the factory lights.

I flip the switch inside and the light on the switch turns on but my fogs didn't.

I checked the fuse inside and it is fine and there is power going to it.

Then I checked the power to the foglights. Blue factory wire is positive and the black is negative, correct? So I should be able to put my negative from my volt meter on the black wire and the positive on the blue wire and get 12 volts correct? I got nothing. So then I tried just the positive and grounded my volt meter on the unibody and still had nothing.

So now I am stumped?

Do I just hook my positive fogs up to the blue factory wires and then ground both of the negatives from the fogs to the unibody while leaving the factory black wires just sitting there?

What would be causing me not to have power coming to the fogs if the fuse is fine and getting power and the switch is lighting up when flip it to turn on the fogs. Could my switch be bad even if it lights up. If so what/how can I test that? Could it be a bad relay. There are 2 of them but how do I check them, I have a volt/ohm meter. Those are the only things I can think of but I don't know how to check them.

It is just weird because before this one of the factory fogs worked. Sorry this is so long but I figured I would tell everyone what I did so far. Any help with pictures if possible would be greatly appreciated.

Thanks!!:banghead: :banghead: :banghead: :banghead:

this maybe a stupid question, but are you testing with the head lights on?

bfred said:

this maybe a stupid question, but are you testing with the head lights on?

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Not a stupid question at all. I tried with just the parking lights on, with the headlights on and I also made sure the brights were NOT on.

I would check power at fuses first. The one in pass. kick panel should power switch and trigger to relays. I believe there are also fuses under the hood to for the actual power to the lights. Next make sure you have power to relays. Should be diagram molded into relay case so that you can tell which terminals have power. hope this helps

bfred said:

I would check power at fuses first. The one in pass. kick panel should power switch and trigger to relays. I believe there are also fuses under the hood to for the actual power to the lights. Next make sure you have power to relays. Should be diagram molded into relay case so that you can tell which terminals have power. hope this helps

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The fuse inside on the kick panel has power and the fuse is good because I checked that right away.

Where is there a fuse under the hood for the lights?

I know where the relays are for the foglights also, and there are 2 of them. There are letters and possibly numbers molded next to the connectors on the relay itself, it that what you are talking about? I don't know what terminals to test though to see if either one is bad or good ?

Standard automotive relay ID's are usually 30-power 87-acc. 87a-acc.closed circuit(probably not used in this case) 86-trigger 85 ground.They should be labeled on the bottom of the relay right next to terminals.30 should be your power,86 power from switch and 87 is wire to fogs. Other fuse should be in underhood fuse box.

If one light is working then the relays, and the switch is good. Your problem either lies in the harness, or the ground. Double check the Blue wire for voltage using the battery terminal as your ground. If you find you now have voltage there then you have a bad ground. If you still don't have voltage then you need to trace the harness back to the PDC. The first place I would look is the splice near the passenger side headlight (it may even be under the battery tray a bit). It is quite common to get corrosion in this area from battery acid.

bfred said:

Standard automotive relay ID's are usually 30-power 87-acc. 87a-acc.closed circuit(probably not used in this case) 86-trigger 85 ground.They should be labeled on the bottom of the relay right next to terminals.30 should be your power,86 power from switch and 87 is wire to fogs. Other fuse should be in underhood fuse box.

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Thanks I will have to check this out later because I am at work now.

scoobyxj said:

If one light is working then the relays, and the switch is good. Your problem either lies in the harness, or the ground. Double check the Blue wire for voltage using the battery terminal as your ground. If you find you now have voltage there then you have a bad ground. If you still don't have voltage then you need to trace the harness back to the PDC. The first place I would look is the splice near the passenger side headlight (it may even be under the battery tray a bit). It is quite common to get corrosion in this area from battery acid.

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One light was working before I put in the new lights, but after I put in the new lights, neither of the lights work. I will check into this later though. I think I am going to try and find the fuse under the hood, does anyone know what fuse that is? I know the one inside is #7, correct.

bfred said:

I would check power at fuses first. The one in pass. kick panel should power switch and trigger to relays. I believe there are also fuses under the hood to for the actual power to the lights. Next make sure you have power to relays. Should be diagram molded into relay case so that you can tell which terminals have power. hope this helps

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OK I found out that fuse 25 15A under the hood is toast. I don't know why it blew because the lights I bought use the same 55W bulbs as the factory ones.

So my question is:
I can have my new lights grounded into the factory black wires that go to the fogs correct? Or do I leave the factory black wire disconnected and just use the power only. Then ground the black wires coming out of my new fogs to the unibody.

Thanks for all the help so far!

You can use the factory black wire to ground, but if it is corroded then the new still won't work. You can also just ground them straight to the unibody, but make sure you sand the spot down to bare metal then use some dielectric grease on the connections.

scoobyxj said:

You can use the factory black wire to ground, but if it is corroded then the new still won't work. You can also just ground them straight to the unibody, but make sure you sand the spot down to bare metal then use some dielectric grease on the connections.

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Thanks for all your help!
I am going to mess with it tonight and see if I can figure out what is going on. I am going to keep my grounds into the factory black wire but if I keep blowing fuses I am going to try a new ground and go from there. You wouldn't happen to know where the ground is for the fogs or if each light uses its own ground would you?

scoobyxj said:

If one light is working then the relays, and the switch is good. Your problem either lies in the harness, or the ground. Double check the Blue wire for voltage using the battery terminal as your ground. If you find you now have voltage there then you have a bad ground. If you still don't have voltage then you need to trace the harness back to the PDC. The first place I would look is the splice near the passenger side headlight (it may even be under the battery tray a bit). It is quite common to get corrosion in this area from battery acid.

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I was a bit wrong on this. The harness goes up the left (drivers) side of the vehicle. There is a connector down in kind of under the air box. I would look there for corrosion, and the grounds are right in that area too. It's hard to tell exactly on the FSM, but they are either the ones by the PCM, or the ones on the radiator support. I'm thinking radiator support though, because I had a grounding issue on a parking lamp once, and that is where it was.

Well I figured out what the problem was. The factory blue wire is actually the negative and the black was the positive. So when I would flip the switch to turn on the fogs the power was automatically grounded which made the fuse under the hood blow.

So basically I had the lights hooked up wrong because I just figured the black factory wire was negative.

Thanks for all the help!