Alta MXR 2019 how to activate 12V electricity at the light aux conector behind the front number plate or find 12V output

Inzell, Germany

I did not find an information / answer to my topic at the forum search.
I have got an MXR 2019 model, and I would like to install lights, LED with very low consumtion, so I would like to take the 12V out of low Volt system to avoid the instalation of a extra 12V battery.
In the front, behind the front number-plate is a small, free conector, named AUX LIGHT, see the attached picture.
The cable comes from the ACM (Accessory Control Module), but there is no electricity, I tryed every switch on the bike and also at active modus.
Has anyone an idea how to activate the AUX LIGHT electricity? Would it be possible with Alta programming tool / Software?
Or is there an other conector / place, where I can take 12V for lights?

Thanks for your Help,



Staff member
If you attach a load to it prior to powering on the bike with the key it will work depending on the load. We haven’t nailed down an exact figure for what does and does not work. I’ve successfully used it to power standard incandescent headlights for testing. I did the same thing you are doing and thought the circuit was inactive.


Well-known member
Newport, RI
The aux connector is a small push in bulb on the EX that is inside the stock headlight, positioned low, same as found on many KTM's, etc.
It's like a running light, low wattage, maybe intended to provide lumens if main headlight bulb burns out?
I use that connector to power a Baja Designs S2 LED headlight from Moto Minded but it initially did not activate due to insufficient load.
I have tried various resistors but have not yet zoned in on it.
The system must see a min load to turn on, then it shuts off if over a max load.
So, for now, we must work within the min and max.
The stock aux light bulb is 4 watts
So, ridiculous as this may sound, I'm running the little stock aux bulb in parallel with LED headlight to make it work for now.
Bought an assortment of resistors from but have not zeroed in yet.
Lots of discussion on "NRC fender eliminator" thread
Inzell, Germany
First, thanks a lot for the good informations!!!,
and now some feedback about my experiences:

I played around a little bit with some small 10W, 4W and 5W lamps on the AUX Light conector on the 2019 Alta MXR.
I put the lamps parallel, more and more.
I messured the voltage and the current, and here are the results: (HV Batterie was full charged)
Min: 4Watt -> 11,87V and 0,342A
Max. 40Watt -> 11,2V and 3,6A
With more lamps, the system shut's down.
If you put away all lamps, I also shut's down.
So one smal lamp has to stay all the time and you can add others until 40W or remove down to 4W.
If you swith the key off and on again everything is reset (after a shut down).


Well-known member
Can anyone confirm whether or not I would be able to power an LED brake/taillight (unknown watt draw) and a LED headlight like the Baja Designs Squadron Sport LED (26 watt draw) headlight off of this lead?

It sounds like this lead requires an aux light bulb (4 watts) in series with the headlight to allow this setup to work.

Would it be possible to use the LED taillight to provide the initial draw the system needs in order to allow the headlight and the brake light to work?

This is the rear taillight/brake light setup that I have, I couldn't find any info on the watts draw but I imagine its got to be low: Baja Designs EFI Dual Sport LED Taillight.


I have an '18 MXR and would like to add a taillight/brake light and headlight to it. I'd prefer not to add a separate additional 12v battery to power everything. I was also reading that the stock Alta wiring harness and lights can be added to the MXR, but I would prefer to avoid that expense as I already have an LED tailligh, wiring harnesses, etc.

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