My new truck came with 6 auxiliary switches that can be used to provide +12V to devices you install in the truck. This capability is primarily designed to give you greater control over accessories like lights, winches, and other aftermarket additions. I thought it would really nice to use one of these switches to power my Ham radio. Currently I just plug in the +12V adapter on the radio to turn it on, and pull the plug to turn it off. I decided to use Aux switch 6 as it was on the end and more importantly I found a YouTube video by a guy who wired up his radios on Aux 6!

So what does it take to wire up one of these switches?

Understanding Aux Switches

Before diving into the installation process, let’s take a moment to understand what auxiliary switches are and how they work. Aux switches are pre-wired and pre-programmed switches integrated into the dashboard of the RAM 3500. Using the commercial settings menu built into the truck’s in-dash display you can control the following settings in each switch:

• Type:
  • Toggle – Switch stays on until you press it again
  • Momentary – Switch is only on while you are pressing it
• State:
  • Default – Switch stays off until you press it, each time you start the truck
  • Memory – Switch remembers the last state it was in when you start the truck
• Source:
  • Ignition – Switch only receives power if the truck is running
  • 12V – Switch receives power whether the truck is running or not

Preparing for Installation

Before I started installing the wiring for Aux Switch 6, it’s essential to gather the necessary tools and materials. Here’s what I used:

1. Wiring harness kit. This was provided with the truck but not installed.
2. Wire strippers.
3. Electrical tape.
4. Crimp terminals to connect the wire ends.
5. Crimpers
6. Multimeter (optional but recommended for testing).

Installation Steps

1. Install Aux Switch Wires: I began by installing the two wiring harnesses into the connectors located under your dash. These are EXTREME difficult to access but with patience it can be done.
2. Locate under-hood connectors: There are two connectors under the hood that connect to the wiring harness that just got installed under the dash. There is a different set of wires with pins already installed that are used in conjunction with the under-hood connectors. Two pins on the lower of the two connectors had to be jumpered. This routes power supplied by Aux 6 back into the dash area. I did not cut these wires, I just installed spade terminals on the ends and coiled them up and secured the coil with electrical tape.
3. Connect Wiring Harness to Aux Switch Wires: I located the wire that ran from the jumpered pins on the connector under the hood and then connected it to the plus side of the 12V adapter I installed. I used insulated spade terminals to connect the wire ends.
4. Test the Connection: Before proceeding further, I tested the connection to ensure everything was working correctly. I used a multimeter to verify that power was reaching the appropriate terminals.
5. Secure Wiring Harness: Once you’ve confirmed that the connection is successful, secure the wiring harness along the existing wiring routes in your truck. Use zip ties or mounting brackets to keep the harness tidy and prevent it from interfering with other components.
6. Test Aux Switch Functionality: I plugged the radio +12V adapter into the +12V receptacle I had bought and pressed Aux 6. Low and behold the radio lit up and made the correct noises!
7. Finalize Installation: Since I was satisfied with the results I needed a place to install the +12V socket. I unbolted the center console and slid it back to gain access to the front. There was a perfect spot right next the USB outlets and there was nothing behind that area. I used a hole saw to cut the opening for the +12V socket and it was a perfect fit. I tightened the socket down and plugged the radio in and did another test. Worked pefectly. I bolted the center console back down and routed and secured the wiring out of sight.

Too long, didn’t read?

Installing wiring for Aux Switch 6 in my 2023 RAM 3500 truck was a relatively straightforward process that greatly enhanced the functionality and convenience of my truck by allowing me to turn the radio on and off with a simple button press. It also opened up the +12V socket I had been using for other uses. ! have 5 other switches I can use. I’m already thinking of added an LED light strip under the hood so I can use that to light up the engine compartment for working in the dark. Maybe a light bar in front and back as well. So many possibilities.