Prewired switch panels and circuit breaker kits make it easy to add exterior lighting to your RV or other vehicle.
By Bruce W. Smith
January-February 2025
Today’s RVs are typically equipped to accommodate comfortable living on the road at whatever level a person might choose. However, one area that many RVers can benefit from is the addition of 12-volt exterior lighting. These come in the form of auxiliary flood lights, driving lights, and fog lights, along with switch setups that make it possible to control them from the driver’s seat.
Adding auxiliary lights and a state-of-the-art rocker switch panel allows convenient control of the 12-volt accessories from the driver’s seat.
It’s easy to find lights. There are seemingly endless sources from which to purchase 12-volt auxiliary lights designed to brighten the world to the front, the sides, underneath, and behind a vehicle. Be it an RV, trailer, car, truck, or other type of vehicle, if there’s a lighting need, there’s a product available to satisfy that need.
Most auxiliary lighting kits, such as those from Baja Designs, PIAA, Hella, Blackoak, Extreme LED, KC HiLites, and others come with their own wiring and switch setup.
However, when you install more than a couple aftermarket lights on your vehicle, the extra wiring can appear messy. The best way to make aftermarket lighting look factory clean and reduce the wiring clutter is to control all the exterior lights from one location and through one power source.
WHAT LIGHTS ARE BEST FOR RV USE
RVers who travel at night can benefit from the addition of aftermarket lights, which reduce eye fatigue and improve safety, especially when rain, fog, dust, or snow come into play.
There are basically four types of aftermarket lights to supplement the typical motorhome or tow vehicle headlights: flood, fog, driving, and spotlights. Each of these has been designed for a specific use, and each one’s beam pattern and intensity of light output has been carefully engineered for that application. LED versions are the best for RV use, because they draw less battery power than bulb-type lights.
Aftermarket lights with a “flood” pattern project a tall, wide beam of light that’s perfect for illuminating an area in the immediate surroundings of the vehicle. They make great work and backup lights when used in an RV. These lights work best mounted high up on the sides and rear of the vehicle. Hella, Amazon, Rigid Industries, and Superbright offer a variety of products.
Fog lights are designed to be mounted below the headlights. Their wide, flat-top beam pattern illuminates the roadway close to the ground without lighting up airborne particles in the line of sight, enhancing visibility when adverse weather conditions reduce driver visibility. Yellow (amber) is preferred over white, because it reduces glare and eyestrain while improving contrast, especially in heavy snow and fog. Good sources of these lights include Morimoto, Diode Dynamics, PIAA, and KC HiLites.
Driving lights boost the driver’s long-range vision, because they are brighter and have a focused beam that extends considerably farther than headlights. These should always be wired into the vehicle’s high-beam controls, so oncoming drivers aren’t blinded by the intensity of these lights. Nilight and Auxbeam are the “budget friendly” brands, with Baja Designs, ARB USA, and Lightforce being the premium options.
Numerous products combine fog and driving light (dual mode) patterns into one aftermarket light, be that a round or bar-type design. Search the manufacturer’s websites for dual- or tri-mode lights and kits.
Wiring into the back of the Painless Rocker Switch is simple and clean.
PAINLESS WIRING
When it comes to custom installation of multiple lighting accessories that operate via a toggle or rocker switch, Painless Performance Products has it covered with a large selection of wiring harness products.
Their plug-and-play switch kits provide everything prepackaged and prewired so all you have to do is install the accessories; connect the wires between the power source and the lights; plug them in; and flip the switch. The wires are labeled, and the instructions are well written so they are easily understood.
I’ve used variations of these prewired kits to install rocker switches in overhead and center consoles of pickup trucks, SUVs, motorhomes, towables, and side-by-sides to control driving/fog lights, flood lights, onboard 12-volt air compressors, and even to activate front and rear winches.
A COMPLETE WIRING KIT
One kit that fits the needs of many RVers is the Painless Performance Products “2011-2018 Jeep Wrangler JK Trail Rocker Accessory Control System” (Part 57000). The $467 kit is easy to install with detailed instructions and a plug-and-play design.
The multi-switch panel can be mounted in the dash, an overhead console, or any other flat surface. (A similar kit is designed to mount under the dash.) Don’t worry about it being labeled for a Jeep; this kit works for just about any “universal” RV/vehicle application that has a 12-volt system — including motorhomes.
The Trail Rocker kit includes the relay center and wiring to power the system.
This kit has five prewired rocker switches mounted in a custom dash panel for a clean factory-installed look wherever it’s placed. The kit provides all the necessary weatherproof splices and heat-shrink tubing to allow for easy direct connection to whatever accessories the switches are controlling.
Also included are two extra “output wires” that can easily be wired into one of the five existing switches, giving you control of even more accessories.
Power to the system is supplied via the Trail Rocker Relay Center, which is also part of the kit. This small housing contains eight 30-amp fuses and relays to provide clean and protected power between your RV’s 12-volt power source (batteries) and the switched accessories.
Inside the
relay are eight fuses that protect the system and provide clean power to the accessories.
To figure how much amp load on the circuit the light(s) pull, divide 12 (volts) into the watt output of the light. Amps=Watts/Volts.
The kit comes with 18 feet of wire, which is usually enough to make the connections between the new lights and the power center. If more length is needed, it’s easy to splice/extend the wires.
INSTALLATION TIPS
Note that this is a plug-and-play kit, making it very easy to install. But mounting the lights, installing the switch panel and relay center, running the wiring between the relay center and vehicle’s battery, and stringing the wiring on to the auxiliary lighting components can take quite a bit of time, so plan accordingly.
Often, the best place to run wiring for your accessories is through the framework under the vehicle.
When installing this kit to power lights in a roof rack on a Class B van, a pickup, or a Class C motorhome, consider running the wires from the switch panel under the carpet, up the driver’s-side B-pillar to the headliner, and through a hole in the roof.
A grommet and silicone sealant applied around the split loom tubing will help keep the wiring exiting the roof tight and dry. It’s also a good idea to run the light’s wiring inside a roof rack to keep it from getting snagged by branches.
Likewise, by running the wiring loom under an RV’s carpet, or behind kick boards and wall panels is one way to keep the installation invisible and the wiring protected. Another is to run the main wiring loom along the inside of the frame rails, then up through the floor, along a wall stud, and through the roof.
Be sure to apply the correct sealant to waterproof any holes drilled into the vehicle’s roof.
SEAL OUT WATER
Whenever a screw or hole is put in your vehicle’s roof, that hole needs to be covered with a self-leveling compound such as Dicor Lap Sealant. All other areas where water intrusion is a possibility need to be sealed with a silicone product such as Dowsil 733 Glass & Metal Sealant or Gorilla Waterproof Caulk & Seal. This includes wiring that runs through the inside of a roof rack.
When the job is done, having full control of auxiliary lights and other 12-volt accessories simply by raising a finger and rocking a switch adds another level of safety and comfort to any family road trip.
RESOURCES
ARB USA
arbusa.com
Auxbeam
auxbeam.com
Baja Designs
catunedoffroad.com
Blackoak
blackoakled.com
Diode Dynamics
diodedynamics.com
Extreme LED
extremeledlightbars.com
Hella
myhellalights.com
KC HiLites
kchilites.com
Lightforce
au.lightforce.com
Morimoto
morimoto.com
Nilight
nilight.com
Painless Performance Products
painlessperformance.com
PIAA
piaa.com
Rigid Industries
rigidindustries.com
Superbright
superbrightleds.com