DRZ-400 USB Install

Adding USB power to a DRZ-400 is a non-negotiable upgrade for any serious adventure build. For this project, the goal was to power a Carpuride Screen while maintaining the ability to charge phones, GoPro batteries, and even a portable tire pump on the fly.

By installing USB ports near the instrument cluster and inside the tank bag—all controlled by a relay tied to the factory ignition—you ensure your gear stays charged without the risk of a dead battery. As a bonus, this setup allows you to run heated grips that automatically shut off with the key, saving you from an accidental overnight drain.

Parts List

• Battery Tender Quick Connect With Fuse: For a clean connection to the power source. (View)

• 4-Pin 12V Relay: To handle the switched power logic. (View)

• 12V USB Ports: Weatherproof units are best for off-road use. (View)

• SAE Plugs: For modular connections (like heated grips). (View)

• Wire: To run power along the frame. (View)

• Wire Connectors: My new favorite connectors. (View)

Step-by-Step Relay Installation

Installing a relay may seem intimidating, but once you identify the “trigger” wire, the rest is straightforward.

Step 1:

Start by installing a fused battery charger cord (Battery Tender lead) directly to your battery terminals. This provides a clean, fused source of power for your entire accessory circuit.

Step 2: Wire the Relay Trigger

The relay acts as a gatekeeper. To make it “switched,” tap into the bike’s rear brake running light as your power trigger source. This wire is typically grey or brown, depending on which side of the terminal you tap into. When the key is turned on, the tail light energizes the relay and opens the power flow to your accessories.

Step 3: Route the Harness

Run your main power and ground wires up the frame toward the instrument cluster. For maximum utility, run a secondary power lead back down the frame to your tank bag.

Step 4: Install the USB Ports

Connect your USB power supplies to the new wiring harness at the dashboard and inside the tank bag. Ensure all connections are heat-shrunk or waterproofed to handle dust and rain.

Step 5: Add a Modular SAE Plug

I recommend adding an extra SAE plug specifically for heated grips. By using a plug-and-play connector rather than hard-wiring them, you can easily disconnect the grips for maintenance or troubleshooting without having to cut into your main harness. Also gives you an SAE plug if needed near instrument cluster.