12V power source in the engine room?

[94_240sx]

I'm trying to find a source of 12V power inside of engine room near battery. I have a pair of Canadian daytime running lights and I want to turn them on when the car starts and turn off when ignition is off. Make sense? Well, I don't know electrical stuff well and all I know is cigarette lighter inside of the cabin and I don't want to run wires all the way from there. I searched, but most people hooked them up to parking lights. Any help would be appreciated.

Here's the pic of S13 Canadian DRLs in case you are wondering.

[Hijacker]

If you want them switched on/off with the ignition, the best thing would be to hook a relay up to the black/red ignition wire. The ignition wire would turn the relay on, and with a dedicated source like the original fog light circuit that does nothing but take up space, you could use that to power the lights through the switched side of the relay. I'll pull up the wire colors of the fog lights as they're not listed in the service manual. I'll also do up a quick MS paint job to better illustrate what I'm talking about.

As for hooking them up to the parking light circuit, that's a bad idea. I temporarily hooked the fogs for my triples to the parking light circuit, and the current draw was so much that it reduced the brightness of the entire parking light system significantly. I ended up repurposing the main power for the pop up switch to run the lights since it was a dedicated 12V line. Ran it through a relay that the pop up switch controlled, and viola, fog lights that didn't leach my running lights.

[94_240sx]

hook a relay up to the black/red ignition wire.

Yes, I need to know where they are located at in the engine room as I have no idea.

I'll pull up the wire colors of the fog lights as they're not listed in the service manual. I'll also do up a quick MS paint job to better illustrate what I'm talking about.

That would be great. Thanks!

As for hooking them up to the parking light circuit, that's a bad idea. I temporarily hooked the fogs for my triples to the parking light circuit, and the current draw was so much that it reduced the brightness of the entire parking light system significantly. I ended up repurposing the main power for the pop up switch to run the lights since it was a dedicated 12V line. Ran it through a relay that the pop up switch controlled, and viola, fog lights that didn't leach my running lights.

Canadian DRLs use 27w bulbs, so they don't use too much power.

[Hijacker]

Found my notes finally. I'm a bit iffy if I remember the solenoid side of the fog relay tying in to the low beam as I've long hacked my custom harness up and changed a ton of functionality on it.

The top picture shows how the wiring was done for the factory fog lights. There should be a plug for a switch in the cabin behind one of the blocking plates next to the steering column. The fog lights themselves sit on a subharness that plugs into a capped 2 prong plug on the main chassis harness. That plug should have an Orange/Black and a Black wire in it.

The lower picture shows how the power to the relay needs to be routed to make DRLs that work when Ign is set to on. If you dig into the main chassis harness next to the relay box on the driver side, you'll find a thick Black/Red wire. That's the ignition switched wire. All you would need to do is take the original wire from the fog relay, Green/Yellow I think, and tap it into the black/red. Then simply send the Orange/Blue wire to ground. When the car is turned on, that relay will turn on. The switched side shouldn't need to be futzed with as you should be able to make a subharness for the DRLs and plug them directly into the plug hiding behind the bumper.

I'm not 100% accurate on the wire colors for the fog relay as it's been about 4 years since I dug into the harness originally to document everything. I just remember Nissan had something simple set up so the fogs were on when the low beams were on. But the beauty of this setup is that since everything already exists in the harness, you just need to make some changes at the relay box, plug a 15A fuse into the fr fog fuse holder, and plug in a blue or green relay.

[94_240sx]

Bart, thank you so much for your info. It helped me a lot. First of all, I already have fog lights on my car, so I can't use factory fog light circuit. I hooked them up right, so fog lights work like factory installed. Here's the write up I did on fog light installation.

how-to-s13-fog-light-wiring-t468396.html

I don't know anything about replys, so I did some research on it. I took one apart, connect it to 12V and tested it. I know how it works now and I understand your diagram as well.




I'm going to add Molex connectors to this guy, so everything will be plug-and-play.


Here's my question. You said there are red and black wires next to the relay box on the driver side.
So I can find them in here?


How about here?


Color is faded, so it's kinda pinkish, but I see a red wire in here as well. There's an arrown that I draw if you look carefully.


Again, thanks for your help.

[94_240sx]

I changed my mind after I figured out how relay works. I thought about keeping DRLs on when the car is running but this is what I want to do. DRLs are on when car starts, but they will be turned off when dim/headlights are on. Actually, that's how Canadian DRLs work. I can use a relay to disconnect the power from DRLs when dim lights are on.

I read this somewhere, but can't confirm. DRLs won't be on when the car starts. They will be on when parking brake is disengaged or shifter is moved to "D" on an automatic car. DRLs will be turned off once dim lights are on.

[Hijacker]

The main ignition switched circuit is a black wire with red stripe (black/red). It'll be fairly thick and in the main group of wires passing through the grommet next to the relay box.

I think the best bet you could go with to cut the DRLs when the lights are on is to use the common ground coming off one of your headlights to drive a relay that cuts the power to the DRLs. The driver's headlamp uses a solid pink wire as the ground (it goes to retract relay 1 to hit its final ground). If you solder a tapped wire into the pink wire and use it to drive a naturally closed relay, it will cut the DRLs when the headlamps are on regardless if it's high beam or low beam. Added bonus is that the DRLs will stay on when the pop up motors are in motion. But I would still recommend running the DRLs through a relay to source their power in the first place. It'll require two relays, but it'll give you the safe functionality you're looking for without encroaching on other systems.

[94_240sx]

Okay, got it. Black wire with red stripe. In a bundle of wires, I noticed some of them were thicker than others. I'm thinking about connecting the relay to side marker or front dim light instead of headlights. Let me see what I can do.

[94_240sx]

I tried to find a thick black wire with red stripe in this mess, but I couldn't. I'm sure it's buried somewhere there. I noticed these wires were running toward passenger side.


And I found it on the passenger side. Is this the ignition wire?


Direct link: http://i126.photobucket.com/albums/p112 ... 1d7721.jpg

[94_240sx]

Okay, I made it work.
This black wire with red stripe on the passenger side is ignition wire.


Getting ready to install.


Here's how I hook it up.


When the car starts, DRL is on.


As soon as dim light is on, DRL turns off.


Not sure if this is a right way to do it, but it works. I will keep my eyes on wires and the relay to see if they get too hot or something.