Aux Switch Live with Ignition Off

[lamokadave]

I have been unsuccessfully searching for an a answer to this question. I need to have an always live 12v source in the front cabin with Ignition off. I'll use this to power my RVI brake controller while flat towing. I recall watching a video maybe related to fog lamps where the installer stated that 2/6 switches could be made to be always hot. It may have involved a switch in the fuse box. Can anyone confirm and provide more detail?

Sponsored

 

[Brian_B]

The common way to do this would be run a fused line to the battery - there are ready-to-use wires already run through the firewall that come out by the glovebox in interior, and over by your fuse box in the engine compartment.

There are plenty of fuses in the two fuse compartments that are always hot. Snag those with an add-a-tap adapter.

ODB2 port is another common place to pick it up from.

 

[cyberfalco]

Yes. I used the already ran wires to have constant 12v in the rear cargo area for my fridge. I didn't use the switches. I just ran connected directly to the battery with a fuse holder.

It would be cool if I could also use an Aux switch but I have not seen a post like that.

 

[Brian_B]

It would be cool if I could also use an Aux switch but I have not seen a post like that.

That would take a bit more wizardry, as the oem aux switches only have power with ACC

 

[cyberfalco]

That would take a bit more wizardry, as the oem aux switches only have power with ACC

My thoughts exactly

 

[Stromad]

There must be a elegant solution for this... I want to be able to use my AUX switches in the rear for fridge and shower/faucet, as well as my future Ursa Minor hardtop camper power and cargo lighting. Baffled that the infotainment can't natively control if each switch is ignition controlled or always hot (with on-board BMS protection).

I've been able to make the 12V socket in my cargo area hot all the time using FORSCAN to disable the Powerpoint Timeout which I use to run a very efficient fridge. This also makes other power points hot when ignition is off but haven't utilized them. Between the onboard BMS cut-off and the fridges cut-off I have zero concerns of draining the battery to any concerning levels and maintaining my fridges 38° temperature.

I have a Dometic CFX5 25 on the way as well as a less efficient Iceco GO20 I've tested on long camping trips for reference (first tested both with a separate LiFePO4 battery and then with Bronco in garage to determine Ah usage). I actually sold my 100Ah LiFePO4 battery due to my low power needs, but may run something like the AAL under-floor solution in the future should my needs change.

 

[CalvinT]

There is a way to modify the upfitter wiring so that switches 5-6 can be used with the engine off, or all six. It's mentioned in one of the threads about retrofitting the upfitter switches.

Sponsored