Automatic Headlamps 2007 Dodge Ram 3500?

[darrollr]

Is it possible to pull an automatic headlamp switch and sun load sensor from a 2005+ Dodge Dakota and install it into my 2007 Dodge Ram 3500? I know the switch is an exact fit and the wire pin out is the same but I don’t know if the sun load sensor can be used in conjunction to make the system a working automatic headlight system. I am wondering and hoping that it may be an easy upgrade like adding fog lights with the preexisting wiring.

I know that there is always the option of installing the 545T Nite-Lite aftermarket automatic headlight system, but I would rather use the factory switch with the “A” setting.

I know that a lot of people don’t care about automatic headlamps but I would like to have them. Has anyone else done this or know if it will work or not?

 

[PuffTheMagicDragon]

I have been looking into the same set up for my 06 1500.

Unfortunately, the control module in our trucks would not be able to recognize the ‘Auto’ selection on the headlight switch from the Dakota.

Each headlight switch selection carries a different ohm resistance back to the module to tell it what to do.

The only inputs our trucks are programmed for are:
660 ohms is Headlights On
2000 Ohms is Headlights Off
1040 (?) Ohms (don’t quote me on this one) is running lights.

The Auto selection from a Dakota carries a 4000 ohm signal to the Dakot’s module that tells it to check the CAN BUS line for the light sensor input.

Since our trucks do not know what to do with the 4000 ohm signal, it defaults to its ‘No Headlight Switch Input’ settings. In the manual it says that setting is something like headlights are always on when the truck is turned on, and the dash lights are always turned to max. (Again off the top of my head, so I may not be exact on the functions)

However, there was a post that I found through the interweb about modifying the Dakota’s headlight switch by removing the 4000 ohm resistor from the circuit board within and jumping the two leads with a relay to an unused lead for the 660 ohm signal. This will give you back control of your fog lights and keep the headlights on whenever the truck is on and turn them off at key off. If you add the Nite Lite unit in line with that relay, you can achieve fully functioning auto headlights in the auto selection as well as proper function of the remaining manual selections.

It would be wonderful if the dealership could flash the LMG Automatic Headlight sales code into our trucks build to let it understand the 4000 ohm input, but thus far I haven’t been able to get a straight answer from anyone. That would be the proper way to do it, however since none of our trucks had the option from the factory, the LMG code may not even be able to be added.

Sorry for the long winded response. And there is a full how to post with all of this information and more (including pictures) out there somewhere if you look hard enough!

Good luck!

 

[HemiLonestar]

I'm curious if this could be an enabled feature that a StarScan could do (like adding fog lights and enabling them to stay on with high beams); OP you close to MD?

 

[PuffTheMagicDragon]

From what I have been told, the StarScan wouldnt be able to activate the option. The BCM would have to have the Sales Code for Auto Headlights (LMG) updated in Chrysler’s system before the StarScan would recognize the Auto function. The problem is, since a grand total of NONE of the 3rd gen Rams had the factory option of Auto Headlights, the LMG code may not be addable at all. Even if Chrysler could force it into the BCM I’ve been told that it could screw with other BCM functions. Also, even if you did get the code in and it didn’t screw with other functions, you would still need to splice in a factory light sensor from another dodge to put the proper signal into the BCM to work the auto lights.

(This all to say I do not believe it can be done through a dealer)

Unfortunately in my area there seem to only be incompetent dealers or dealers that arent willing to help out with things like this, so I’m pretty much talking out my **** here, but I’m fairly certain that I’m right. But if anyone has a friendly dealer that will work with them, I would love to be proven wrong as I prefer factory functions rather than the aftermarket route I plan to go with the 545t kit.

 

[HemiLonestar]

Not necessarily, adding fog lights doesn't require it, nor does altering their function, as well as enabling nav features in the CAN bus. I will say that what seems to work and not work is pretty inconsistent across platforms lol.