Headlight resto-mod

[Peterkor1]

I am re-doing a 1970 w200 pickup with all 2019 ram parts. Full interior, frame, drivetrain, etc. However, I am using a led 7" headlight and a led universal tail light for the lighting on the truck since that's what will keep the older look still. The 2019 ram has the led lights with fault sense for headlights and taillights. So, that is where my issue comes into play. I've adapted a simple harness to get all the lights to work, but I get the bulb out detection because of the fault sense and fast blink in dash. I have alpha obd and have gotten the rear detection shutoff, but haven't seemed to get anything to work yet for the headlights. Any ideas or thoughts on how to proceed?
Thanks

 

[PurpleRT]

I have no clue on the headlight issue but would love to see a build thread.


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[Richard320]

You are suffering from low current draw. Was the donor vehicle LED equipped? If not, I suspect you might be able to tell the BCM it is using alfaobd and then it should straighten out. If it was LED equipped, I have zero guesses.

 

[Peterkor1]

You are suffering from low current draw. Was the donor vehicle LED equipped? If not, I suspect you might be able to tell the BCM it is using alfaobd and then it should straighten out. If it was LED equipped, I have zero guesses.

It’s led equipped

 

[Jimmy07]

I am re-doing a 1970 w200 pickup with all 2019 ram parts. Full interior, frame, drivetrain, etc. However, I am using a led 7" headlight and a led universal tail light for the lighting on the truck since that's what will keep the older look still. The 2019 ram has the led lights with fault sense for headlights and taillights. So, that is where my issue comes into play. I've adapted a simple harness to get all the lights to work, but I get the bulb out detection because of the fault sense and fast blink in dash. I have alpha obd and have gotten the rear detection shutoff, but haven't seemed to get anything to work yet for the headlights. Any ideas or thoughts on how to proceed?
Thanks

Try shutting the fault sense circuits off:
CBC Config I/O Usage: Left Front Lamp Diagnostics Present - Pin F25- NO

CBC Config I/O Usage: Right Front Lamp Diagnostics Present - Pin F28- NO

 

[Peterkor1]

Try shutting the fault sense circuits off:
CBC Config I/O Usage: Left Front Lamp Diagnostics Present - Pin F25- NO

CBC Config I/O Usage: Right Front Lamp Diagnostics Present - Pin F28- NO

Unfortunately they are already set at NO. So, why from the factory it would be on NO but still senses a fault I am not sure. I wouldn’t suppose you have any other thoughts since I hear you’re the lighting guru on these forums haha? Possibly branch off some fault sense wires from the main (small white with brown tracer) to each of the circuits that have the fault sense? Any help is super appreciated.

 

[BlueHemi1500]

You have one of the best sources of AlphOBD in the thread. I doubt other users will be of much source of info other than the programmer who lives in Russia, and I'm not sure how to reach him/her for help.

BlueHemi1500

 

[Peterkor1]

@Jimmy07 a little update. I tried branching off the fault sense wire to those lights that required fault sense, but that didn’t work either. Any chance you’ve thought of anything else to try to trick the fault sense wiring or eliminate it completely? Thanks in advance.

 

[Jimmy07]

@Jimmy07 a little update. I tried branching off the fault sense wire to those lights that required fault sense, but that didn’t work either. Any chance you’ve thought of anything else to try to trick the fault sense wiring or eliminate it completely? Thanks in advance.

If those settings are set to no in the BCM, then the fault sense wires are disabled. Sometimes the BCM just doesn’t like certain LED lights, and you just have to wire in resistors.

 

[Peterkor1]

If those settings are set to no in the BCM, then the fault sense wires are disabled. Sometimes the BCM just doesn’t like certain LED lights, and you just have to wire in resistors.

@Jimmy07 So, from the factory those settings were set at no. Before I did any modifications to the wiring, just unplugging headlight, it showed in the dash-headlights, blinkers, etc were out. Does that make any sense to you? So, from my thinking it tells me that the fault sense wires are still detecting even though it's set at no. I've got new old school led headlights working for their proper functions, just want to eliminate that fault sense so it doesn't pop up in the dash whenever I use them.