How to Install a Light Bar on a Pickup Truck

Consider where you want to put the switch. Every vehicle is different and everyone has their own preferences, so put the switch in a location that suits the specific vehicle being worked on. Look for somewhere that is easy to reach but not in the way and will look as clean or stock as possible.

Remove the plastic dash panel. After deciding on a location, the next step is to access the back of whatever panel that the switch is being installed in. Every panel is different so research the vehicle to see the specific instructions on how to remove the panel. Most panels have easy plastic clips that just need to be depressed to remove the panel. This can be accomplished with a clip removal tool. The panel may also be held in place with a screw so a screw driver may also be needed to remove those.

• Research your vehicle online or on YouTube to ensure you're not going to damage anything by trying to do this incorrectly.

Mark the hole for drilling. Now that there is access to the back of the panel it should be easier to see where the best location to drill the hole for the switch is. Mark that location with a marker.

Drill a hole in the dash. Drill a hole for the switch where the mark is placed, using a drill bit that is just as big as the inside diameter of the switch so it can just barely fit in the hole. This will ensure a snug fit and prevent the switch from rattling around.

• If you're tossing up between two drill bits, choose the smaller one, and test the fit. You can always drill a larger hole, but you can't put it back.

Install the switch from behind the dash panel. Take the backing nut off the switch and place the switch inside the hole that was drilled. Ensure that the side with the actual switch is facing outward toward the vehicle cab.

Tighten the switch. Once the switch is in place reattach the nut to secure the switch to the panel.

Determine where to run the wire. Now that the switch is installed, look through the vehicle and determine where the best path for the wire from the light bar to the switch is. Run a wire from near the battery through the firewall (the metal wall between the engine bay and vehicle cab) to the switch that was installed. From the switch, the wire will be run to the installed light bar along the vehicle frame and then up in between the cab and the bed of the vehicle to the light bar. Ensure that the wire will not be in the way of any moving parts of the vehicle.

• Wherever possible, try and use pre-existing holes and follow pre-existing wires.
• Keep the wire away from the engine, as the heat may melt and ruin the wire.

Drill any needed holes. Drill any holes that are needed for the wire to be run through any metal (firewall to engine).

• This step should not be necessary in most situations, as there should already be many wires running through ports in the firewall that you can use.

Run and secure wire. Run the wire along the path that was determined earlier. Ensure that the wire is secured enough so that it won’t move but not so tight that it damages the wire insulation.

• Use zip-ties if necessary.

Connect the switch to the wire. After the wire is run to the switch in the cab that was installed earlier, connect the wire from the battery to one screw on the switch. To attach the wire, use the wire strippers to take off about ¼” of wire insulation and wrap the bare section of wire around the screw on the switch and tighten the screw until the wire is secured. Repeat the connecting process with the end of the wire that is being run to the light switch from the other screw on the switch.

• If your switch has three prongs, attach it to the middle one and one of the sides, preferably the 'On' side of the switch (if it's labelled).

Connect the positive wire to the light bar. Use one of the automotive butt connectors (Crimp/ Heat shrink style) to connect the positive wire to the light bar wire. The red wire is the positive.

Connect the ground wire to the light bar and vehicle. With the positive wire connected to the vehicle, the light bar will need a ground wire connected to it. After the positive wire is connected, use the remaining automotive butt connector (Crimp/ Heat shrink style) to connect the ground wire to the light bar wiring. Black is ground. Find a location to attach the ground wire to a metal surface on the vehicle. With the location selected cut the ground wire to the necessary length and take one of the automotive connector eyelets (5/16 Hole) and crimp them to the other end of the black negative wire. In the location that was selected earlier for the ground wire, drill a hole and secure wire to the metal surface using the one 1-inch bolt (5/16” diameter) Tighten the bolt using adjustable wrenches.

Reinstall the switch panel in the cab. With the switch connected to the wire, reinstall the panel that it is attached to by reversing the disassembly process to install the panel.

Add wire connectors inside the engine bay. The wiring from the engine bay back to the light bar is complete, so it is time to attach and connect the fuse. The fuse has two short wires connected to it: one can be connected to the battery and the other is connected to the rest of the wiring. Attach the remaining 5/16 eyelet connector to the end that is connecting to the battery. On the remaining end attach an automotive butt connector (Crimp/ Heat shrink style).

• Make sure you use a fuse to avoid ruining your light bar if there's a problem with your battery or elsewhere in your vehicle's electronics.

Connect the fuse to the wire. Connect the positive wire to the fuse with an automotive butt connector (Crimp/ Heat shrink style). Attach wire with fuse in a safe location in a way where it can be attached to the positive end of your vehicle battery.

Double check your work before connecting to battery. Look through what has been done so far and ensure that everything from the light bar to the fuse is connected properly as described.

Re-connect the battery. Connect the eyelet ending wire from the fuse to the positive terminal of the battery. Repeat Part 1, Step 1 instructions in reverse to reconnect the battery.