Up here in Canada you have to have daytime running lights on your vehicle. I will be putting HID's in at some point but don't want to run them hooked up all of the time because HID's are either on or off. So I wanted to rewire the fog's as daytime lights. Have any of you done this?

 

Why not run the HIDs? They cost less to operate than incandescents, and have much longer bulb life.

 

First I know this is an old post but I was wanting to change my DRL so they are off the headlights and run the fog lights.

As a note for the quoted question, DRL run at around 75% and will damage the HID if connected to DRL. (I also have a 99 expedition and the DRL work off the dims, location is Canada)

Does anyone know of an illustrated example of the wiring that needs to be changed around or do I just go off the tech manual wiring diagrams and search?

 

The easy way to do this, is to change the wiring in the main headlamp switch, so the fogs are on any time the key is in the run position, but this removes the ability to turn off the "DRL" by turning on the parking lamps.

The DRL resistor circuit is in series with the normal headlamp circuit, before the main headlamp fuse in the fuse panel.

In the case of 99-03 MY trucks:


Depends on how much you want to change, I'd have to look at the DRL cell again, but it might be a case of cutting the DRL resistor circuit, and splicing it into the fog lamp circuit ( Need to verify this, have not looked in some time do not cut away yet, unless you have the diagrams, could disable your headlamps ).

Let us know if you want to dive into trying to use the DRL circuit, or if you want to go with the hot in run position activation of the fog lamp relay.

 

Thanks for the quick reply,

I'm hoping it could be as simple as splicing and swapping the wires on the DRL resistor behind and below the driver's side headlight but I just want to be sure before cutting. I could run a tester and do a bit of splicing but I hate to end up with a lot of soldering (I dislike having a bunch of splice connections that can possibly give me issues later). Forgive me but I'm just going to think out loud here and you can point out my errors.

Here are the diagrams I'm working with;

Looking below at 97-1, when the vehicle runs (Current through fuse 5, for the relay and fuse 9 is the actual current for the DRL) and the lights are NOT turned on, then there is no current running to splice 244 located near E. When the lights are turned on then voltage is directed down the splice and into the solenoid in DRL relay-1 turning off the current for the DRL and allowing the connection in relay-2 to connect with F.




Below in 97-2 you can see that the resistor is reducing the current prior to entering the relay. Being that it is like this, I'm thinking there is no benefit touching any wiring at the resistor unless I just want to jump it for full power but that’s another issue for later.

At points B and C, the current is delivered to the headlights. Because the relay dictated the current is either from the DRL or full power from the switch and feeds back to fuses 26, 27 and 28 then I see it being impossible to route a simple splice under the hood to disconnect the headlight DRL connection and attach the fog lights.

I would almost have to splice wire 1033 RD/VE (point F) and bypass the relay, then by cutting wire 13 RE/BK and connecting the splice. I then would have to connect the cut wire from wire 13 coming out of relay-2 to the fog lights after the switch.







Looking here at 86-2, the main dash light switch controls the grounding of the low voltage current allowing the activation of the higher current off the relay. So the next question would be if I want to have the fog lights turn off when the headlights are turned on or the brights turned on....

 

There is also the issue of the Autolamps and if they will effect anything when tampering with the original wiring.

 

And a better look at the main switch;





OR.... Would it be better just to pull the relay and power fuse for the DRL and install an aftermarket DRL module to the fog lights and call it a day????

 

Not running through a resistor, but how about this for simplified ?



using the 5 pin auto relay ( both 87 & 87A contacts ) use the normally closed contacts to provide power to the fog lamp relay coil ( behind the main headlamp switch ) turning the fog lamps on any time the key is in the run position ( any hot in run position circuit will do with an add-a-fuse, CJB position # 5 15 A is a Hot in run position fuse which the add-a-fuse can be installed in ).

When the Parking lamps are turned on, the coil in the auto relay ( the one added, not the fog lamp one ) opens the Normally Closed contacts, and the hot in run position power is no longer to the fog lamp relay coil.

The DRL fogs lamps turn off with the parking lamps on, and then the normal fog lamp switch operation is used to turn the fog lamps on / off.

Not running at a diminished power output, so that is one thing to keep in mind ( if a DRL needs to be less then full power ?? ), but it is much easier to add / trouble shoot ( everything is done behind the dash by the main headlamp switch ) and return to stock if you want to.

Just a thought, let me know what you think of this.

 

Wow, your a genius.. That is exactly what I was trying to figure out.

So, just for my sake so that I am strait with it. I would first disable the DRL by disconnecting the DRL relay block and use the loopback plug (F4SB-14489) or just make my own, then install a secondary relay behind the BJB under the dash following your diagram.

I can splice the "Hot in Run" (Pin 30) to the post fuse wire ( 295 LB/PK) off fuse #5. I then run off Pin 87a to a splice into the fog light relay wire (188 WH/BK). The solenoid off the added relay (Pin 85) would be connected to the wire (14 BN) which operate the park lights and Pin 56 would be to the ground.

Or would it be better to connect before Fuse 5 and add a seperate 15a fuse?

Kevin

 

That sounds correct, less I would use an Add-A-Fuse in the Fuse 5 slot.



This is just my method, much easier to find the tail on the add-a-fuse, then trying to find the wire behind the CJB while standing on your head on the drivers side. It is a bit tight back there with the GEM ( this is a 99-03 MY truck right ? your EVTM cells lead me to infer that ), trying to split the loom open, and find a single wire in the 30 to 50 that are back there.

If you have your fog lamps on, and turn off the truck, the Normally closed contact is still open, so you cannot feed the fuse #5 with the fog lamp relay fuse #27, so that is safe operation.

That is about all I can see for easier install, is using the add-a-fuse, other wise this should do the trick.

 

Excellent...

Thank you very much SSCULLY, you saved me time and my knuckles!