Radio headunit- headlight trigger question

Still looking for a heaunit that lets me choose when to change display Brightness; dont want to be required to use a headlight trigger.
Can I rig my own trigger circuit switch [instead of headlights]?

 

Pretty much any aftermarket headunit these days has its own brightness control built into the unit.

 

As far as a switch to trigger the dimmer I'm sure someone smarter than I could figure out how to rig one up, in theory it'd just be putting a switch on whatever wire goes between the headlight switch and the radio dimmer trigger, but idk that might be done via canbus or something not as simple as just a wire. As far as head units go, I think most have the ability to turn on/off the dimmer in the settings. I was just looking at the new Alpine iLX-W770 and it has that ability. Briefly looked at the manuals of a couple others, the

$349 Kenwood DMX709S eXcelon 6.95" Capacitive Touch Screen, Car Stereo, CarPlay and Android Auto, Bluetooth, AM/FM HD Radio, MP3 Player, USB Port, Double DIN, 13-Band EQ, SiriusXM

Kenwood DMX709S and the Sony XAV-AX3700 and both have the ability as well. Best bet is to go on Crutchfield, pull up the head units page, open the manual, and do a Ctrl + F for "dim" and see what settings the head unit has.

 

thx @frichco228 & @Snert.
I should have noted the reason i prefer to enable/disable Bright/Dim from a separate switch is that I dont think hunting thru 2-3 menus to adjust the display as Im driving is either safe or convenient. I don't like the headlight switch trigger either, since on fog/snow days, headlights are mandatory on most fed & state hwys and thus renders a DIM display on an otherwise bright day. As well, there are those times at nignt when you pull Into a brightly lit mall or gas station and you'll need to turn lights off to brighten display...
So, the idea of a "ME" control switch [anywhere convenient] to DIM/BRIGHT the display when I want it.
I see that the Alpine ilx407, 507 button panels have an ambient 'light sensor', which I guess might be the best built-in solution but it remains to be seen how well that performs.
The only other solution would be if the industry would create an assingnable shortcut key that would step thru Brightness levels via a 'Long Press' button and subsequent presses to achieve display preference.
[tongue-in-cheek]:
But! ...and this is a really BIG BUT, that would mean the industry would have to trust USER judgement of 'what is a suitable display brightness for the current conditions?'
"...Im afraid I cant do that Dave."..."this mission is too important for me to allow you to make that change currently. Please manipulate the parking brake first."

 

Just a thought, but I wonder if you called iDatalink if that's something that could be programmed to one of the steering wheel buttons.

 

would be nice and would be a big feature around here, but...i dont have SWC.

 

Hip-shot: seems to me the headlight trigger wire of a given HU operates on sensing an energized circuit [not sure, but likely electronically]. So one way or the other, would appear a simple 'in-line SPST' [between HL wire & HU trigger wire] might do it?