The Baja Designs 640176 is an add-on harness that enables the amber backlight on LP Series lights, covering the LP9, LP6, and LP4. It suits owners who run LP lights without any backlight wiring and want to add the feature to an existing setup. Instead of replacing the whole harness, you get only the backlight leg, so your current low and high beam wiring stays in place. Before ordering, confirm you have a non-Sport model, because the manufacturer says this will not work with LP Series Sport models. The kit includes four common fuse taps, an alternate splice connector, and zip ties, which gives you more than one way to power the backlight from a circuit that is already on. This makes it a practical option for buyers who want the amber glow without tapping into random wires. Searches for LP9 backlight harness, LP6 amber backlight wiring, and Baja Designs fuse tap install will bring you to this exact part.
The harness uses bullet connectors and is designed for universal fitment. The manufacturer notes that the harness is long enough to reach the fuse panel or to splice into keyed power. Keep in mind that owners on user forums sometimes find the run longer than they need and have to tuck or cut the excess. The LP-series wiring sheet lists an operating voltage of 12-36 volts for these lights. Mounting hardware is not included, and no switch comes with the kit, so you will need to choose how the backlight is controlled.
No. The manufacturer states that this harness does not work with LP Series Sport models, so check your light version before buying.
No. The manufacturer lists no switch with this harness. Owners on user forums commonly run the backlight through a factory auxiliary switch so they can turn it on and off with the lights.
Per the manufacturer's instructions, you use a circuit test light or multimeter with the key off to find which side of the fuse is powered. If both sides show power, the manufacturer says to choose a different fuse location.
Per the manufacturer's install sheet, this is a fuse-tap job that most DIY owners can handle with a circuit test light or multimeter and a flathead screwdriver. Open the fuse panel cover and use the diagram on the cover or the owner's manual to identify candidate fuses. With the key off, test each fuse to confirm which side carries power, then set the tap in that fuse position and plug the harness into the tap. The manufacturer's guidance is to route the backlight harness along the existing LP light harness so it reaches the plug, then secure it with the included zip ties. If no fuse works for your vehicle, the splice connector is the fallback. Owners on user forums have warned that some fuses stay energized for a while after shutdown, which can leave the backlights on longer than expected, so verify the fuse behavior before you finish. Also plan for extra harness length, since owners have found the run longer than needed.
