I'm looking to eliminate the stock Daytime Runing Lights system, and change it so that the fog lights are simply run off the stock switch. Switch goes on, lights go on, switch goes off, lights go off.

Looking at the FSM wiring diagram of the CPU (page T-33), +12V goes through a fuse, and then into the fog light switch, and then into pin 4k on the CPU harness. Following whatever happens in the CPU, it exits through pin 4i, which leads it to the coil of the fog relay. On the other side of the coil there is another 12V source. Well if I understand electronics correctly, for the coil in the relay to work it needs -12v on one side leading to a ground on the other, this means that the wire coming OUT of the CPU leading IN to the relay is a switched ground (controlled by the CPU). When the CPU signals a ground, fog lights on.

Now here's the plan, and I need a guru to check it. I plan to go all the way back to the 12V that leads into the fog light switch. I plan to pull the power, and hook it to ground. The wire at pin 4i, and 4k will be cut and spliced together. This means that a constant 12v will be fed to the coil of the relay, and the ground will be on the stock switch. When the switch is closed, a ground is supplied to the coil, giving power to the switch which leads to the fog lights.

Does this work? Am I doin alright!?

MY GOD that was long. I appologize for the read, most of which was unnecesary. it's late and I'm not thinkin'.

Thanks folks.

 

Aren't DRL's a legal requirement in Canada? Why would you want to be able to turn them off? Just curious.

With your method the system will now be fed battery power all the time, so they won't turn off unless you flick the switch. I see flat batteries in your future...

 

Trust me. Been there, done that. You won't always remember the switch, and you'll drain the battery. Usually at a very inopportune time.

A better solution would be to add a switch inline with the ECU signal. If the switch is closed, the system will function normally. If the switch is open, the lights won't come on because there's no path to ground. This has the benefit of still letting the computer turn the lights off when the car is shut off.

-=Russ=-

 

Ya.. in Canada they can up with the thought of day time running lighht a little while back and I remember having to install them on older model cars ..it's a safety issue I guess..they don't really enforce the issue around my area but I myself feel safer knowing that if I have "lights" then someone ahead of me should be able to see me and not cut into my driving path unintentionally.Handy,usefull and looks cool.I am going to put mine to switch on by the key.I have a nasty habit of leaving the lights on during the daytime even though they stick out like a sore thumb!...they sell head light reminders..maybe they know me!

 

Maybe you can mimic the USA system?

 

I See The Front Fog Light Relay. Where Is The Rear Fog Light Relay?

 

Its not on North American Spec FC's. Only Euro and Aus/NZ (and possibly JDM- don't know for sure on the JDM thing).

 

THE POST WAS MEANT AS HUMOR. WHY CALL IT THE FRONT FOG LIGHT RELAY WHEN THERE IS NO SUCH THING AS A REAR FOG LIGHT (HOPING THERE ISN'T ANYWAY).

JUST FOG LIGHT RELAY WOULD HAVE BEEN FINE.

 

Because there is a rear fog light relay on some models.

If you were an engineer laying out the electrical, and you had two versions, one with a rear relay and one without, wouldn't it be easier to just not list the rear relay on the one without a rear relay.

 

I just dont like how they turn off when the high beams go on. Id like to be able to control them. I usually drive at night anyways so id see if they were on when I get out of the car.

I just need to know ifthe circuit would work guys, not what you think about the idea. there isnt much left on my car that IS legal

 

oh and to avoid confusion, you are all convinced that I want a switch to turn them OFF, this sint true. The CPU shuts them down when the high beams go on, I want to be able to keep them on all the time for low visibility moments! now stop getting mad at me!

 

Chill man, nobody's mad.

Personally I wouldn't care about this since when you're using the high-beams the fog lights are pretty much redundant. But if you really want this, here's a much easier way.

A wire from the low-beam headlight circuit runs through the fog light switch to the DRL control module in the CPU. When the CPU sees 12V from this wire, the fog lights are on. When the high-beams turn on the low-beams turn off, and this then turns the fog lights turn off. All you have to do is cut the red/green wire at the fog light switch and connect 12V to the switch side of the cut wire .You can get that 12V from the blue/black wire on the adjacent mirror control switch. This will tell the DRL module that the low-beams are always selected. Everything else should work normally. Both the DRL unit and mirror switch are fed from the ignition switch, so when the ignition switch is off the fog lights will switch off too.

BTW, you should be looking at the proper wiring diagrams when figuring out this sort of stuff. That schematic in the Body Electrical chapter only tells you half the story.

 

awesome thanks a lot man. appreciate it!

 

does anyone know of an online source with the "proper" wiring diagrams?

 

I just cut the feed from the headlight switch and picked up the IG2 feed from the window fuse to the fog light switch.

I think daytime running are a good idea - they see you comming.
My avatar shows the results.

 

I agree, DRL are wonderful.

Im in a valley in BC. I work at night, and we get these occasional super crazy mad foggy nights, where even with high beams its hard to see. I want to be able to use high beams AND fogs at the same time, which is not possible with the stock system

awesome, you sig links to the wiring diagrams im looking for too. thanks sureshot

edit: nevermind, doesnt go detailed enough in the n/a diagram. Need page E-1, 2

 

Judging from the picture provided, it appears that the relay is triggered by the low-beam headlight power. To make them work ALL the time via the headlight switch, I would simply disconnect this wire, and route it instead to the parking light wires instead. As it shows in the Diagram on page 1, this wire is R/B, should see +12V. In my opinion, the easiest method to do this, would be to disconnect this wire at the foglight switch inside the car, and run it to one of the dash lights (even though you can dim the power, it should be enough to trigger the relay I would believe), but I'm sure someone else can chime in on that.

Don't you just have to disable pin 2J at the ECU to disable the DRL? The CPU only functions for the security system I believe. Actually I'm pretty positive this is the case.

 

that picture was for the American version I think. Im dealing with the Canadian DRL circuit

 

It's the exact same. You just disconnect the wire at the ECU to disable the DRL. Then, to make the fogs come on with the lights, disconnect the wire at the switch for the fogs, and run that instead to a different light source (such as the cig lighter light, or you could go all the way up to the switch if you wish), this will allow the fog light relay to function whenever the lights are on, rather than whever the low beams are on (since in the diagram they are wired to the low beam light power source to trigger the relay)

 

alright yeah I see that. on pin 2J Canada is a ground and Everywhere else is 12V. so shouldnt I be connecting it to 12V instead? or just disconnect it at the ECU.

 

Just disconnect it

 

awesome thanks man im doin this tongiht.

I <3 SonicRaT

 

That's pretty much exactly what I just said to do, except I suggested a much more convenient place to get 12V from. Ten minutes work and no need to access the ECU.

Nope. The CPU controls the turn indicators, hazard lights, headlight and ignition key reminders, ignition and door key illumination, stop light failure warning (S4), seatbelt warning, horn, alternator warning, security system (S5) and DRL system (Canadian S5). That's why it's called the Central Processing Unit. If it just controlled the security system, it would be called the security system unit.

 

Yeah, I was refering to it's functions with the headlights though. I believe the only thing it has to do with the headlights is for the security system. Oh, and I mentioned using a light as the +12V source simply because then they'd be on only when the lights are on, (parking or otherwise), rather than having them on anytime the ignition is on, personal preference is all.

I can't seem to figure out if the ECU triggers the relay for the DRL, or if that's the CPU's doings, but then I can't understand why the ECU would be involved at all if that were the case, maybe I should try to locate the CPU section and find out more on that pin and what it does.

 

I went ultra ghetto to do this, I tapped into the yellow side marker light +12V and ran it to the relay that activates the fog lights (in front of the crossmember). I disconnected the "on switch" for the fog light relay and hooked up the tap from the side marker light. So anytime i turn on my parking lights, the fog lights turn on too. If i turn on my high beams, the fog lights stay on as well.