The Diesel Stop banner

Constant 12V Power in the Cab,

17K views 15 replies 5 participants last post by  jchipper 
#1 ·
I'm looking for a good constant 12v power source that is already in the cab.

I want to make the Aux Switches always hot, and also thinking about making one of the 12 power outlets always hot as well, so my phone can charge with the key off.

any suggestions as to how to get power without running a wire from the battery, I would like to avoid running a wire through the firewall if possible, thinking there has got to be a good power source somewhere in the cab like maybe near or at the fuse box or something? any thoughts?


Thanks!
 
#2 ·
Look for the white with violet stripe near the park brake. It is hot all the time. It will be a blunt cut wire taped to the bundle.
 
#3 ·
oh ok sounds good! if it's blunt cut I assume that it's a fused circuit just for users to use as they like. any idea what which fuse it is?
 
#4 ·
The wiring diagram doesn't show a fuse. It is the same wire as used for the park brake. Maybe you can check your manual to see if there is a fuse for the park brake.
 
#7 ·
Humm so if it's for the parking brake why does it have a blunt end? blunt end usually means a customer access wire right?
 
#6 ·
yeah I could... wonder which circuit to tap into
 
#8 ·
It is the same wire (color) that feeds the park brake but there is a splice prior to the park brake for the blunt cut wire.
 
#9 ·
ok, thanks
 
#10 ·
Ok so I checked it out today and its only hot when the key is on. after the key is off it stays hot for 10-15 mins and then it's off.

there are some "unused" fuse spots in the passenger side fuse box that have fuses in them and seem to be hot all the time. any idea how to tap into those circuits? I'd like a clean install by tapping into that wire but if all else fails I could always use a "add a fuse tap adaptor"
 
#11 ·
Why not attach to one of the power points or cig lighter....they are hot all times and fused at 20a...you could use the one under the rear seat...it might be the least used one in your truck
 
#12 ·
it's a thought
 
#13 · (Edited)
Here's the Rundown of what I ended up doing,

In the passenger side fuse box there are a number of unused fuses so I ended up using these Add-a-circuit Fuse TAP Adapter Mini ATM APM Blade Fuse Holder from amazon
[ame]https://www.amazon.com/gp/product/B01DYQM6EO/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1[/ame] and put a 10 Amp fuse in it and soldered a wire onto it and ran the wire over to the the Aux Switches, to access it I removed the 110V outlet and then was able to reach my hand around behind the switch panel and pop it out and I cut the Voilet wire ( #8 position on the back of the plug) and taped the cut end back to the loom then soldered and shrink wrapped the wire from the fuse panel and now the entire panel of Aux (Upfitter) switches are always hot so they can be used anytime with the key on or off, Perfect! I used a product called "Painless Braided Sleeve" they have multiple sizes but I used the 1/8" wire it fits a single wire just perfect and gives the install a very professional factory installed look. [ame]https://www.amazon.com/gp/product/B001P29XZK/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1[/ame]

then while I was at it I ran a wire with the same painless sleeve from the pass through wires in the engine bay along the frame rail to the back of the truck, I used the 1/4" size and was able to fit 2 wires (one is a spare for use later). I used exactly 20 feet for that run (truck is a Crew Cab Long Bed) and I installed some LED Lights in the bumper. hope this helps someone, overall it turned out to be a very clean professional looking install, which is what I wanted.

as a side not it's so nice to work on a brand new truck! no dirt no grease just clean and new :p
 

Attachments

#14 ·
Nice clean install and work!!

Thanks for sharing
 
#15 · (Edited)
Just a FYI that could come in handy.

When I went looking for an always on power supply I tapped into the red wire on this connection under my drivers seat. It is a high amperage wire probably for the power for an inverter or seat cooling that my 2012 truck doesn't use.

It was easy to use a seperate fuse for the circuits that I ran off it it and it was easy to run the wire under the carpet up under the dash.
 

Attachments

#16 ·
ok good to know. thanks for the info
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top