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Discussion Starter #1
On another forum someone figured out how to disable the auto headlights on Canadian '03's. This will also work if you have the auto climate control since there are seperate light/solar sensors in the dash module.


He found that you can remove the dash to get to the sensor and insert a 8.8 ohm resistor between the black and white wires after cutting these wires from the sensor. Fools the BCM into thinking it's daylight all the time. This is similar to the pre-03 trucks although that was a different resistance resistor that was used for those years. The other two wires feed the auto climate control signal and are left as they are, connected to the sensor on the dash.


Instead of removing the entire dash and associated parts, I found in a schematic that the white wire is landed on the BCM at J3-A4 and the black wire at J4-B7. I believe that J3 is the middle connector on the BCM and J4 is the right connector. Someone may want to verify this. I know that J2 is the left connector.


I haven't tried this yet, but if someone really wants to eliminate the auto headlights for good, whether it be Canadian or US, I think this is the ticket.
 
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The daytime running lights would still be on while in gear.
 

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Discussion Starter #3
yep.
 

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That's info I was looking for- I won't have time to try it untill next weekend but I'll let you know if it works!
 

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Once you turn on your headlights the DRL's go off then wouldnt they after the resistor is installed?
 

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Discussion Starter #6
The operation of the DRL's should remain the same as factory. If you wish to have them on with the headlights then you'll need to do the relay trick that others have done to put the low and high beams on at the same time by using diodes.

The only thing the resistor will change is that the auto headlights are disabled when it gets dark because it makes the BCM think it's daylight all the time.
 

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Discussion Starter #8
I believe this is what will be needed. Try at your own risk.
 

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What if you could simply pull up on the sensor on the dash, clip the wires and tie them together...? Would this fool the sensor?
 

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Discussion Starter #10
You can try to get at the wires on the topside but I don't know if there will be enough slack to work on them there. If you slip it could drop down into the abyss behind the dash too. :help2:

Connecting the wires together won't override the signal and will cause the headlights to be on ALL the time, even during daylight. The BCM needs to see a certain resistance (provided by the sensor or resistor) to know if it's light or dark out.

I've been meaning to do this mod for quite some time and need to get after it before hunting season as well as ice fishing season when it's dark by 4:30. I just keep forgetting to do it until I get in the truck and have to crank the dial over to shut the lights off and then I swear a little under my breath and continue on.
 

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Well, what I couldnt quite understand was the actual wires under the dash....There's supposed to be a black one and a white one that you could connect together to get the desired result, which is I think I'm after...

I just want to simply disable the sensor completely....I hate it, I hate it, I hate it and do not need a friggen sensor to turn my lights on for me...

If someone could pin point the actual wires under the dash, I'd be willing to try it.
 

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Discussion Starter #12
Look at the schematic I posted. Also the first post in this thread. There are two harnesses that you need to find under the steering column. Removing that panel will help you see what you're doing, otherwise you can lay on the floorboard and look up and see them too.

Find the J3 and J4 harness/plugs that are connected to the BCM under the steering column. On plug J3 you'll need the white wire at location A4. On plug J4 you'll need the black wire at location B7. If I recall, A is the top row of wires on the plug and B is the bottom row. There maybe only one white wire in the entire plug so that should narrow it down quick. Rotate the wire around a little to make sure there isn't a tracer line on it. Same with the black wire.
 

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Discussion Starter #13
Here's the BCM connectors
 

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And thats it?

Once I find the wires, snip, and connect together?

If someone could take a picture and circle the actual wires, that'd be great...
 

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Discussion Starter #15
You'll need a resistor. I've read that some people have used a regular ol' paperclip and that was enough resistance to work. When I heard of this a while back the guy used a 8.8 ohm resistor and he claimed it worked too.

I did this procedure on my '02 but that didn't have the solar sensor which is used for automatic climate control. It only had one ambient light sensor for the headlights. These new trucks with auto climate control have a dual-purpose light/solar sensor (four wires from the sensor on the dash instead of two).

Since this is the case, you will need to retain the black wire and not just clip it and tie it to one end of a resistor because this is the ground for the solar sensor as well. You will need to TAP into the black wire with the resistor. From what the schematic tells me the white wire CAN be clipped and then the resistor connected to the end of it. (see schematic I posted). When you clip the white wire, go back from the plug as far as you can so that you have some wire to work with incase you want to go back to factory some day.

You may be able to push the resistor wire into the black wire socket too...not sure if there is enough room to wedge it in there if that's how you want to leave it. Might be worth trying for testing purposes.
 

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Shew....Dont know if I'm willing to do that....I'm not that good with wires to begin with...
 

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Discussion Starter #17
Ha. Now that you stirred my interest in this again I may have to give it a go one of these days.
 

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If you do....maybe we could do it together...Or over the phone so you could possibly walk me through it.
 

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hopefully this works because it would save me some $$$ by not having the dealer reflash the bcm
 

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Minn-Kota;1922548; said:
I did this procedure on my '02 but that didn't have the solar sensor which is used for automatic climate control. It only had one ambient light sensor for the headlights. These new trucks with auto climate control have a dual-purpose light/solar sensor (four wires from the sensor on the dash instead of two).

Since this is the case, you will need to retain the black wire and not just clip it and tie it to one end of a resistor because this is the ground for the solar sensor as well.

Nick, you dont have the climate control option anways, so you dont need the resistor from what I'm reading...
 
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