How-to: Wiring the Auxiliary Switches on the 2021 Ford Bronco

This thread is for those of you wondering how to connect your auxiliary lights to the pre-run wiring locations and auxiliary switch bank on your 2021 Ford Bronco! The aux switch bank is standard on Wildtrak, First Edition, Badlands, and Black Diamond Broncos and an option on Base, Big Bend, and Outer Banks.

Ford did an awesome job putting several "Accessory Ready” mounting locations all around the Bronco, and below is a writeup on how to connect to your aux switch bank using the Diode Dynamics OEM Auxiliary Switch Harness. I hope you find it helpful!

• Locating the Pre-Run Factory Wiring (0:28)

If you go to the owner's manual in the features tab of your head unit, you'll see that Ford has provided a full wiring diagram showing the exact locations of all the wiring for our auxiliary switches.


We love the fact that Ford has gone the extra mile to route the wiring to different “Accessory Ready” mounting locations around the Bronco including the grille, the fenders, and the rear quarter panel.

• Identifying Wire Colors & Amperages (0:49)

In the owner’s manual, you will also find a table listing each aux switch and its corresponding wire color and current draw rating. Be sure to check the amp draw on your auxiliary lighting to ensure the switch is rated appropriately for the light.

• Connecting Auxiliary Switch Harness (1:01)

Using the Diode Dynamics OEM Auxiliary Switch Harness, connect to your power wire. Using wire strippers, remove enough insulation to make a good connection. Insert the wire into the butt connector and crimp it to secure the connection.


Then you’ll want to locate a factory grounding point for the black wire.

• Routing the Harness (1:36)

Route the harness to your auxiliary lights and test to complete the installation.


As you can see our OEM Auxiliary Switch Harness makes it super simple to install auxiliary lights using the factory accessory-ready mounting locations on the Bronco.


If you have any questions, please don't hesitate to post, PM, or email [email protected].

PM us for the free-shipping code (U.S. forum members only)

John C.
Diode Dynamics