Splitting DRL and Turn wire

Hi all,

Canadian Dodge challengers come with amber DRLs combined on a single wire with the front turn signal out of the body control module.

I am importing them into Australia and we need to remove the DRL feed from the BCM to be purely indicator flash only. Unfortunately not something I can program out of the BCM.

I cant get a signal from the stalk as its CAN and id like to use mosfets/transistors/solid state relays if possible.

I need a "simple" circuit made with DIY parts found in my local electronics store.

Any ideas how to get this to work?

My initial idea was a normalled closed relay which opens only when the BCM cuts power to flash the turn. The issue is that when the BCM cuts power at night or when the head lamps are turned on, the indicator feed will be constantly on.

Appreciate your help.
Ben

This is an electronics forum and I for one have no idea what a DRL or BCM is.

Mike.

DRL is a daytime running lamp. Its just an LED light so it make no real difference as to what its purpose it.

Its a 12v electronic circuit, hence why im asking electronic experts and not car gurus. Car guys generally dont understand complex circuits.

The BCM is the computer that controls the car. Its called a body control module.

What year is your Challenger?
NOA Dodges you can usually disable the DRL with dealer tool and some good aftermarket ones. In Canada they can not do this legally I have heard so they may not offer it as a service.

Not as familiar with the challengers but I have worked on many dodge modules from early 2000's til recent years and have indeed turned off/on DRL diagnostically. They are usually not on here in the states so people would have me turn them on. Modules from Canada are always on and people usually ask me to turn them off

Can't you just remove the LED?

Mike.

Pommie said:

Can't you just remove the LED?

Mike.

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I'm presuming the LED is the actual indicator light - the front ones of which are permanently ON (as DRL) - and flash OFF when used for indication.

As already suggested, it seems highly likely that it can be disabled using the correct dealer equipment.

They're picky about the daytime running lights, but are okay with having the steering wheel on the lefthand side?

I wonder if a simple signal inverter would work. It essentially reverses whatever the input is. DLR on signal in = off out. Turn flasher pulse on and off giving a signal. Should be fairly simple to implement I think. The pros here have a better idea on how to make it carry the needed current.

Thanks for all your replies.

Dealers wont change the region coding to disable the DRL.

Its a single 12v output from the module that controls the on/off function of the single LED light.

As explained before, inverting the signal will work, until the module turns the DRL off when its night time or the headlamps are on. When that happens, the indicator feed will be constantly on.

Will an OBDII interface work. Available Here fairly cheaply.

Mike.

Pommie said:

Will an OBDII interface work. Available Here fairly cheaply.

Mike.

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Unfortunately no. Its feature is unavailable to be switch off without reflashing the BCM to change the country code to America, which they wont do. We've already asked numerous Dodge dealers who state that its top level authorisation as its rewriting the VIN designation.

We have dealer connect, witech and techauthority as a dodge dealer but still no access.

Does the vehicle have any lights anywhere that are purely directional indicators? If nothing else, and assuming that the turn signal indicators on the instrument panel are accessible, then you could take a signal from there, and use it to control front lights.

Can you disconnect the original DRL/flasher circuit from the indicator lamps and wire in a conventional flasher unit?
T49 = 12v supply to flasher unit.
T49a = to center pole of the stalk switch.
T31 = ground.
As the stalk switch is likely designed for low current signals and probably not able to supply enough current to directly drive a lamp, you may need to add a relay for each of the left & right circuits.
T30 = 12v supply
T87 = lamp output
T85 = ground
T86 = input from turn signal (stalk) switch (l or r) - duplicate this for the other side.

EDIT: scratch that - there is insufficient load on the flasher unit, from the relay coils.

What is the part number for module you need to configure? You keep saying BCM but all the lighting controls I am used to on dodges are in the FCM (front control module) for older stuff and TIPM's (totally integrated power module) on newer stuff, with the message from the switches sent through the cluster via data lines.

I'm taking it that its a fairly new model 2018/19? Most of the early models(2000-2015ish) can be done even with an autel 908. You can also just do it manually by simply swapping a few bits in the eeprom memory.

Witech should be able to do it for you if you have it. I have a walk-through to add/remove the options using witech somewhere, I'll see if I can find it. Unless Canada's system is completely different I do not see where there could be any type of blocks that prevent you from resetting the module and re-configuring it the same as you would do when replacing it. Keep in mind this is not the same as "flashing" it, which only changes the core programming so a Techauthority subscription wont work for this. You need the actual wiTECH subscription from FCA. DRL, VIN, Region, these are all just configuration options. Same as how long your lights stay on after you cut the car off, or if your want your horn to honk when you push the lock on remote.


Worst comes to worst and if your close enough ...just drive it across the border and have it taken care of at a competent independent shop, I bet many around the boarder are familiar with your problem. Trying to hack up the wiring will likely end up with quite a few DTC's and dummy lights on the dash.

narkeleptk said:

just drive it across the border and have it taken care of at a competent independent shop, I bet many around the boarder are familiar with your problem

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Unfortunately, the Canada-Australia border is heavily controlled and monitored—barbed wire, machine guns, search lights—due to the current animosity between the two countries. The forged paperwork that would be required just for a person to cross over, let alone a car, makes it way too impractical.

BobW said:

Unfortunately, the Canada-Australia border is heavily controlled and monitored—barbed wire, machine guns, search lights—due to the current animosity between the two countries. The forged paperwork that would be required just for a person to cross over, let alone a car, makes it way too impractical.

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Luckily he needs USA configurations and our border is close and freely crossed for anyone who wishes to enter. Unless you try to do it legally, then you may have to wait a few months for the paper work first.

narkeleptk said:

Luckily he needs USA configurations and our border is close and freely crossed for anyone who wishes to enter. Unless you try to do it legally, then you may have to wait a few months for the paper work first.

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I guess it depends on where the car is at the moment. I have this vision of the OP in the car—windows open—mid Pacific Ocean—paddling towards Australia. Damn. That kinda sounds like fun.

Are DRLs forbiden in Australia? I understand that they're not required, but would be surprised that they would be illegal.

My car has them. I bought it used in Utah where they're not required, but not prohibited. It was originally sold in New York. I just figured that the original owner needed them for travel into Canada.

It appears that DLRs are optional in Australia. See https://www.racq.com.au/cars-and-driving/safety-on-the-road/driving-safely/daytime-running-lights

Mike.
Edit, is it the dual purpose that is the problem?

I have played with arduino & can.
There is probably a code to turn off the running light and another for indicators.
An arduino and a Mcp2515 interface is what you need to 'talk' to the light, and some programming knowledge.
With just the lamp on the bench you can send it sequential codes, eventually it'll do what you want.
This is assuming the light has some intelligence in it, if not then you could put togther some circuit that only allows a maximum on time after which it turns off, allowing it to flash but not remain on for longer than a second or so.