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      DC-DC Charger Installation – Final Wiring Steps

      This section covers the final steps required to complete the installation of your DC-DC charger. Follow all instructions carefully to ensure a safe and reliable setup.

      1. Vehicle-Side Wiring

      1. Route the provided vehicle-side wiring from the vehicle battery to the back of your vehicle, close to the 7-pin socket.

        • Important: Ensure the cable is routed away from sharp edges, moving parts, and hot surfaces such as the exhaust. Use protective loom, conduit, and zip-ties where necessary.

      2. Install an 80A fuse or breaker on the positive wire.

        • The fuse/breaker must be installed as close as possible to the vehicle battery.

        • This protects the circuit against short circuits and overloads.

        • This breaker is installed inside the trailer as well, but another one is still required near the vehicle battery for safety. You may use a fuse instead but this is the recommended option.

      3. Connect the positive wire directly to the vehicle battery terminal.

        • Do not splice into secondary circuits.

        • Ensure all connections are tight and corrosion protected.

      2. Charger Signal Wire (Required for Early Trailers)

      A signal wire is required to enable charging. This is factory-installed into the trailer on 2026 models and onwards.

      1. Route the signal wire from the charger's pin 1 location to a 12V+ power source. When the charger is installed in to the trailer, this opening is located on the side facing your fridge area. Recommended power-feed options:

        • Marker light power inside the 7-pin junction box.

        • DCDC Charger input power (same source as the main positive feed).

          • Note: If this option is chosen, your charger will turn on as soon as the main cable is plugged in and the optional switch is turned on. This can result in accidentally draining your battery if you do not unplug the DC DC charger or disable it via the optional switch (see below).

      2. Install an inline fuse on the signal wire.

        • Recommended fuse size: 5A.

        • Recommended wire size: 16 AWG.

        • Place the fuse close to the power source.

      3. (Optional/Recommended) Install a switch on the signal wire.

        • This allows manual control over charger activation.

        • Position the switch in an accessible location inside the trailer.

      3. Factory Pre-Wired Signal (2026 and Newer Trailers)

      • Starting with production in 2026, trailers are pre-wired with a switched, fused signal connection to the marker light power.

      • If your trailer is from this production year or later, no additional signal wire installation is required, only the vehicle-side wiring.

      Final Checklist

      • Vehicle charge wire routed safely and protected with loom or conduit.

      • 80A fuse/breaker installed at vehicle battery.

      • DCDC Charger positive cable connected directly to vehicle battery.

      • Signal wire installed, fused, and switched (if required).

      • All connections tight, insulated, and corrosion protected.

      • If assistance is needed, contact warranty at warranty@offgridtrailers.com

      ⚠️ Warning: Incorrect wiring may damage the charger, trailer battery, or vehicle electrical system. Always double-check wiring and fuse ratings before powering on.

      DCDC Charger manual (Dometic DCC-1212-40): https://www.dometic.com/externalassets/dcc1212-40_9600003755_100277.pdf?ref=-1263071748