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Switched power source?

JoeN

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I’m adding some 12v and usb outlets to power my dash cm and some other accessories that I want to power on and off with the ignition or accessory setting on my 2019 3500 Big Horn.

I thought I’d be smart and use one of those fuse tap wires on the main fuse box under the hood — but haven’t been successful.

Figured I would copy other folks’ methods.....But after doing some searching I can’t see that anyone else is tapping into switched power like this? Maybe my search mojo is failing.
 
If you're doing what I think you're describing, which sounds like you want to simply rob power from an existing fuse positive side for whatever you're trying to run, you might want to have it power a relay instead

If you power a relay through an already existing fuse that is on during ignition, you can then run a new circuit from battery to whatever you want through the relay. That way you won't be adding extra amperage draw through whatever you're robbing power from. Just be sure you're wiring is a good size and that circuit is protected as well

My bighorn came with the extra button bank and harness that has been described in other threads. This bank allows you to add pretty much whatever you want, then program the buttons through the computer yourself to make them momentary, on, off, etc
 
Yeah, if I had the choice I would have got the upfitter switches option, but...... didn't have the choice so I don't have that on mine.

Powering a relay and using that to manage the switched power of a new direct fused connection to the battery sounds like a more robust option than using the "add a circuit" fuse adapters.

I'll do some research to learn how that works in detail.

Thanks!
 
I mean you could just run a circuit from an empty but ignition-on-actuated fuse slot, and put a mechanical switch inside the cabin instead of using a relay. All I was saying is if you were hijacking an existing circuit you should probably power a relay at basically no amperage in order to provide higher amperage power to whatever you're running

There are several ways to do it legit, and several more ways to get it to work but be kind of half- hearted

That and you never know if any of this canbus stuff is going to throw a code if it doesn't recognize something. I had the worst time trying to get some xenons in my last ram to work even with relays because the computer couldn't deal with not being able to recognize the missing halogens
 
Yeah, if there was one actually live empty fuse slot that would be a smart option. Near as I can tell with a volt meter, literally none of the empties are hot constant nor ignition triggered.

Definitely want to "do it right" since it is not much harder to "do it right" and that's safer and more reliable, imo.
 
No 12V receptacle in the cab of your Big Horn? I was sure that they all came fitted with at least one and as such, there are myriad gizmos/gadgets available to expand the OE 12V receptacle to combinations of 12V cigar + USB or otherwise.
 
I think I misspoke. There is one, in the dash. I want another, more out of the way, so that I don't want a pile of wires running all over the dash, powering the trailer camera, GPS and dash cams.
 
If you’re going to be using low power stuff there’s a cable available from infotainment.com that plugs in behind the 12v outlet in any Chrysler vehicle and adds a T with a fuse.

Look in the “miscellaneous“ section of their site.

IMG_3060-2_1024x1024.jpg
 
I have one 12v "cigar lighter" type receptacle on the top of the dash in my '19 3500 that I plug my radar detector into. I installed my dash cam and did not want to tap into any fuses or anything like that, so I ran the wiring that came with it down under the passenger-side front dash (along the roof line and down the a-pillar) and ended up in the center console by the USB connections. I searched for and bought a USB-to-12v connector (see pic) and it plugged the dash cam into it. No fuss...no muss!

20200128_135421[1].jpg20200128_135401[1].jpg
 
If all of the Chrysler products have the same plug on the back of the cigar lighter/power outlet then Quadratec sells this for Jeep Wranglers. I have one in my wife's JL and will be getting one for my truck also.
 
Question maybe this group can answer. I can start a new thread if more appropriate.

I want to power a cell phone holder that also does wireless charging. When I use the usb banks in the front (those with both USB A and USB C together) it doesn’t work. It turns out the port is only temporarily powered if I plug this device in. It will turn on for 3 seconds, then shut off. So while the phone is attached it starts charging for 3 seconds then stops for 30, then charges for 3 seconds, etc. almost seems like the truck logic is testing for a certain draw, not seeing it and shutting down the power.

So I have to find another power source. I want this all done clean behind the dash. I was thinking of taping the 12v lighter plug but will need to remove the entire 12” radio to do it. Not adverse to this, but if it can be avoided… Other option is to add a USB port tied off a currently switched source behind the lower dash.

My question is whether anyone knows of a 10W-capable switched source behind the driver side dash to tie into.
 
Kind of late....but my cig lights is constant is there another switched source in the cab?
 
Kind of late....but my cig lights is constant is there another switched source in the cab?

The fuse that controls that is a yellow 20A fuse. It has two positions it can be put in. F90 is how it comes from the factory which is always on / Battery. Moving it to F91 changes it to switched / ACC.


Sent from my iPhone using Tapatalk
 
The fuse that controls that is a yellow 20A fuse. It has two positions it can be put in. F90 is how it comes from the factory which is always on / Battery. Moving it to F91 changes it to switched / ACC.


Sent from my iPhone using Tapatalk
This worked for me, moved fuse and now my off-road GPS shuts off with ignition. THANKS.
 
On the newer trucks you should've received a bunch of harnesses if you have factory aux switches. It's the grey plug (if I remember correctly) with 2 wires that are lopped back through different pins on the plug. One of those is an ignition power source and the other is constant. I used the ignition for my weboost and I'll probably use it for more accessories in the future. Getting the plug in there under the dash by the parking brake is a major pain if you have big hands like me, but its doable. Once plugged in you've got a few options to tap into for in-cab power.
 
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