Click for Coverage
Due to the EU’s Global Data Protection Regulation, our website is currently unavailable to visitors from most European countries. We apologize for this inconvenience and encourage you to visit for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more.MOTORTREND.COM
  • JP Magazine
  • Dirt Sports + Off-Road
  • 4-Wheel & Off-Road
  • Four Wheeler

Painless Performance kit makes wiring in auxiliary lights easy

Posted in How To: Electrical on June 28, 2017
Share this

Wiring is a dreaded task for many off-roaders faced with installing switches to control multiple auxiliary lights and accessories. Figuring out what gauge wires to use, what type of relays will handle the load, what fuses are needed, and where to mount everything can be mind-boggling.

We are among those who have an aversion to amps and colored wires. We’d rather be knee-deep in mud pulling out a winch cable than laying upside down under a dash with wire crimpers in our hand.

So instead of sitting down to sketch out a wiring diagram and sourcing all the wire, fuses, and relays to make the installation of a lightbar, foglights, backup lights, and eventually roof lights on our ’91 project Bronco, we took the easy route and turned to Painless Performance Products.

Painless Performance Products Universal Trailer Rocker Control Box (PN 57005) is prewired to make it as easy as possible to install six auxiliary switches in a vehicle. Wires are labeled and color coded.

They have had a slick solution to wiring in just those sort of things in Jeep Wrangler JKs for a couple years with a kit called the Trail Rocker Accessory Control System. The relays, fuses, and wiring leading to a six-switch panel and to the accessories are pre-wired/installed into one control box that mounts under the hood. It even comes with a switch panel specific to mounting in a JK.

It’s a huge hit with the Jeep crowd. Now Painless offers a similar kit for the rest of us who need wiring help. The Universal Trail Rocker kit uses the same control box and wiring, but doesn’t come with a switch panel.

Painless offers a complete array of switch panels and rockers. But we needed one that was easy to install and inexpensive. So a little web surfing led us to a cool six-rocker switch panel used in boats that worked just fine in our 4x4 land yacht. It’s from Proelectric. The rockers are lighted, labeled, and pre-wired, taking the guesswork out of that part of the installation.

Mat Johnson, a buddy who spends his work hours at Mobile Diesel Service working on wiring and electrical systems for big rigs, and his weekends wheeling his not-so-stock Toyota Tacoma with us, set up our Bronco with the Painless Trail Rocker kit. The photos show how easy it is to do wiring when you have this kind of kit to simplify the process.

The best part of this installation is the Painless Trailer Rocker Control Box makes it simple to wire in accessories on any vehicle, not just Jeeps, and never be worried about the system failing because you chose the wrong fuses, relays or wiring, or erred in how everything was wired up.

Inside the relay center are eight 30-amp relays and fuses to handle a variety of wiring needs from lights to air-lockers. There’s also extra spaces to add two more relays and fuses if your system needs to expand.
The mounting bracket on our kit still had the mounting brace for a JK. A quick hit with a cutoff wheel removed the excess, which wasn’t needed for our installation purposes.
The relay center needs to be mounted as close to the battery as possible. So we mounted it to the passenger-side fender on our fullsize Bronco. We had to move the smog canister a couple inches closer to engine for the Painless box to fit. Only two wires needed to be hooked up: one to battery hot, one to battery ground.
You’ll never be short of running wires to the accessories. The accessory harness wires are 20-feet long.
The wires coming out of the Painless relay center to both the switch side and to the accessories are printed with the switch number and color-coded making it easy to know which switch controls which wire. There’s no guesswork involved.
We used a step-bit to punch a hole in the lower floorboard of our Bronco to feed the wiring loom from the relay center into the cab on the passenger’s side. The wiring is then ran under the dash and out through where the ashtray used to reside.
We found this pre-wired marine rocker panel on Amazon for $30. It has six waterproof rocker switches and it’s pre-wired. All we needed to do was plug a Painless wire onto the open spade terminal of each switch.
It didn’t take our buddy Mat Johnson very long to wire up the switches. Painless’ printed wires and color coding made that part of the inside wiring well, painless.
One of the standard items in off-road wiring is protecting the wires from getting cut or scuffed by rubbing on any sharp metal. We used split-loom to protect ours.
Another good procedure to follow is covering all wiring splices with heat-shrink. Mat used a butane lighter to seal the deal.
Here’s a neat trick for owners of older trucks with ashtrays like in our ’91 Bronco. Remove the ashtray and cut a 5-inch muffler clam diagonally to make a clean, strong mounting bracket for the six-switch panel. Mat made ours and riveted it in place.
We used machine screws to bolt the Painless relay center to the inner fender just aft of the battery, and kept the extra wires tucked tight in case we add more accessories down the road.
Our switch panel up and running. The Painless Control Box makes such an install easy even for a first-timer tackling such an upgrade. Now our old truck has USB charging ports and a voltage to go with lighted switches for our lights and accessories.
As they say, rock on! Painless Performance made it easier than we imagined.

Amazon Affiliate links are our attempt to show you real-world pricing and availability for the products we review and install, and while the Amazon links are separate from editorial and advertising, the Four Wheeler Network may receive a commission on purchases made through our posts.


Painless Performance Products
Ft. Worth, TX 76105
Mobile Diesel Service

Connect With Us

Newsletter Sign Up

Subscribe to the Magazine

Browse Articles By Vehicle

See Results