Nilight LED Light Bar Wiring Harness Kit — 15 ft 2-Lead 12V with Relay & Fuse

Nilight's 15 ft LED light bar wiring harness kit is a ready-to-install 12V wiring solution with two output leads, relay, blade fuse and an illuminated on/off rocker switch for safely powering up to 180W of off-road or work lights.

This harness supplies a long, factory-style wiring run from a dashboard switch to remote LED light fixtures. It bundles a 15-foot main cable, two light output leads, a power relay for safe switching, and a blade fuse for overcurrent protection. Designed for use with 12V systems, the kit speeds installation and reduces the need to splice in your own relay or inline fuse, making it a practical choice for automotive, marine, and utility lighting projects.

How will this harness simplify installing off-road LED lights?

The harness centralizes power switching and protection so you don't need to add separate relays or fuses. It brings the switch close to the driver while carrying current over a long, protected run to the lights. Pre-made terminals and connectors reduce installation time and wiring errors.

• Includes a prewired relay to handle high current safely
• 15 ft main cable lets you place lights far from the switch
• Two output leads for connecting dual light fixtures without extra splices
• Blade fuse for circuit protection against over-current or shorting

What compatibility and power limits should I consider?

This 12V harness is suitable for most cars, trucks, SUVs, ATVs and boats that use a 12-volt system. Each of the two leads supports a combined maximum load; the manufacturer recommends limiting total draw to keep wiring gauge and relay ratings within safe limits. If you plan to run multiple high-wattage bars, verify combined wattage does not exceed the kit’s rated capacity.

• Designed for 12V electrical systems typical in vehicles and boats
• Two outputs share the relay and fuse—keep combined wattage below kit rating
• 16 AWG lead wiring suitable for moderate loads; extend with proper gauge if needed
• Universal connectors fit most aftermarket LED light bars and work lights

Which parts of the kit protect my vehicle’s electrical system?

The harness integrates safety components to reduce risk to your vehicle’s wiring. A power relay shifts the switching load away from the dash switch, the blade fuse isolates overcurrent events, and the illuminated rocker switch gives an easy visual status of the circuit. Together these features help prevent switch overheating and protect existing wiring runs.

• Power relay handles high currents so the dash switch carries minimal load
• Blade fuse interrupts current flow during a short or overload
• Illuminated rocker switch shows on/off status for quick checks
• Pre-terminated connectors lower risk of poor crimp or loose joints

How long is the harness and can I extend it?

The main harness measures approximately 15 feet from switch to the wiring tail, providing ample length to route through cowl, firewall and along chassis. If your installation needs additional reach, you can extend runs using appropriately rated wire and connectors while maintaining proper gauge and secure terminations. Use heat-shrink and protected routing to keep new sections reliable.

• Approximately 15 ft of main wiring from switch to outputs
• Extendable with matching gauge and secure connectors if required
• Routing options: firewall pass-throughs, chassis clips, and fender wells
• Follow best practices: fuse near power source, protected routing

Who this is for: This Nilight 15 ft wiring harness is made for DIYers, installers and vehicle owners who want a safe, plug-and-play style solution to power one or two LED light fixtures from a single switched 12V source. It fits automotive and marine installs where a long run, relay protection and a visible on/off switch simplify wiring and reduce installation time. If you need to power many high-wattage bars, consider using additional relays or higher-gauge wiring to match your total load.