headlight issue - need help

[14CTD01]

So i tore apart the headlights this morning and re wired them correctly instead of the grounded to the frame method and actually used the corret connectors aswell.
While i had the lights unplugged, i disconnected the cab light wire at the switch and tested the system. Still the same result. Switch doesnt change anything, no cargo, dimmer or parking lights.

I plugged everything back up and put it back together except the new switch and i tested resistance to ground to all the wires at the connector. When i tapped the only wire on the 2nd row, my cargo light dash icon turned on. Sure enough the actual light was on too. I tapped it again with the probe and it turned off. So now i know it works.
Did the same thing on every wire and noticed some wires will allow the dash to come alive so its triggering the computer but no other lights would turn on.
I plugged the switch back in knowing the cargo circuit works and hit the button, fullt expecting it to work and nope, it activates the gauges such as key on ACC but no light. Still no other switch function controls anything.

Though maybe it was a bad ground so tested that and its got zero resistance to the frame so thats fine.
Im at a loss.
The orange wire that powers the switch has 5.5 volts going to it, im not sure it thats good or bad. Since the canbus system doesnt use full load on the wires for sensors and switches i assume thats normal.

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[14CTD01]

I know the or/br wire is the main power, does anyone know what the white wire with brown is to or from?
Ive got the same 5.5v going to it now as well.

Wothout the swtich plugged in, when i turn the key the or/gr lights up 12.5 volts, and 0 with the key off. It seems like its being back fedd somewhere but i have no clue where that white wire goes.

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[14CTD01]

Additional issue:

Instead of trying to control the lighting circuit, i decided to try and find out what was controlling it and back track from there.
So i started with fuses thinking i could isolate the fused system powering the lights.
The lights are controled by the BCM (cbc as noted on the fuse cover)
I pulled the fuse for ext lights, lights still on with key "on"
Pulled next cbc fuse (there are 4), still on, pulled all 4 and the headlights are still on. How are these lights getting power with the BCM completely powered off? Is there another fuse or way it gets power?

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[watersupply189]

Additional issue:

Instead of trying to control the lighting circuit, i decided to try and find out what was controlling it and back track from there.
So i started with fuses thinking i could isolate the fused system powering the lights.
The lights are controled by the BCM (cbc as noted on the fuse cover)
I pulled the fuse for ext lights, lights still on with key "on"
Pulled next cbc fuse (there are 4), still on, pulled all 4 and the headlights are still on. How are these lights getting power with the BCM completely powered off? Is there another fuse or way it gets power?

Is there a relay to the headlights wired directly to the battery? Doesn’t make sense you pulled all the fuses and the lights are still on?


2016 Ram Laramie 3500, G56, 6.7, MM3 by Double R Diesel, Rough Country Leveling, 35x12.50 Nitto G2, HID headlights and fogs plus many many other add ons.....

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[14CTD01]

Negative on the secondary relay.
All of the wiring is factory.

I did some further testing of fuses and the #4CBC fuse for power locks would kill the headlights, however the dash lights still dim and the cab lights stillactivwte when the key is on. Im beginning to think its the BCM itself that is bad and mixing signals.

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[watersupply189]

Negative on the secondary relay.
All of the wiring is factory.

I did some further testing of fuses and the #4CBC fuse for power locks would kill the headlights, however the dash lights still dim and the cab lights stillactivwte when the key is on. Im beginning to think its the BCM itself that is bad and mixing signals.

Hmmmm very interesting. Do you know the history of this truck? Was it ever a flood vehicle, wrecked or something else?
Could be a bad BCM...


2016 Ram Laramie 3500, G56, 6.7, MM3 by Double R Diesel, Rough Country Leveling, 35x12.50 Nitto G2, HID headlights and fogs plus many many other add ons.....

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