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How To Choose Lights For Your Trailer

Trailer lighting helps keep your trailer legally registered with your state’s Motor Vehicle department. Additionally, safety is important. They allow other drivers to know where your trailer stands and your intentions. In dark conditions and poor visibility, having a set of functioning trailer lights is your best protection against collisions (especially rear-enders), and serious damage to your boat. Trailer lights should be of high quality. You should consider them an essential part of your boating safety gear.
How trailer lights work

Trailer wiring consists primarily of a plug connecting to the vehicle’s lighting circuitry. It also includes a matching connector on trailer. The trailer wiring also includes a wiring diagram that runs the length the trailer frame. Additionally, there are a variety side, tail, and stop lights around the perimeter.

Multi-function light fixtures can combine several functions into one compact fixture. They may include both lighting and reflector functions. This makes wiring lights and mounting them much simpler.

Shining in a Hard, Tough Environment

Regularly, trailer lights suffer from the following:

The effects of cold water submerging hot or warm lights can cause thermal shock. Submerging the light bulbs in water can result to short circuits. This can also cause corrosion of connections and sockets. It can also burn out filaments and cracks plastic lenses. Saltwater has the most severe corrosion.
Get covered in road grime which can get into your connections.
The effects of highway vibration can be damaging, breaking and weakening incandescent bulb filaments.
A drop of voltage is caused by high current draws from many lights. This can be from the towing car all the way to trailer taillights.
Protruding light cover that attracts hard objects such as fences or high curbs.

Trailers greater than 80 inches wide

Trailers with less than 80′ width are exempted from the legal requirements. Larger trailers must have more lights than smaller ones. Trailers less than 80′ in width are required to have side and rear reflectors as well as tail, stop, turn, and marker lights. You will also need a license plate lamp. For trailers exceeding certain lengths, additional side markers lights and side reflectors might be required.

Trailers with a width of more than 80″ require additional lights to define their perimeter. Three red identification lamps are required at the rear. They are sold as one bar with the lights installed at the correct spacing. This is similar to the tops of tractor trailer rigs or the rear of trailers. Clearance lights, designed to inform drivers of the width and location of your trailer are required on all sides. They should be located as far outboard from the trailer fenders as possible.

Matching an existing light set

Perhaps a quick fix can be all you need to get your lights on the right track if they don’t light up. Make sure to clean the mounting bolts with a wire brush before buying replacement lights. Most lights are wired to the trailer’s frame via the mounting hardware. Lights that don’t work can be caused by poor or bad ground.

If you have a history of trailer light problems, and your current lights are looking pretty worn out, we recommend replacing them all. An inexpensive new light kit that includes a wiring harness can be purchased for as low as $25 and can usually be installed within an hour. A box section trailer frame can make it difficult for wires to pass through. To avoid this, you might need to pull a messenger through the vehicle before pulling out all of the wires. Take out the trailer plug and attach the new harness. Remove the old harness carefully from the trailer’s rear.

Wiring Color-codes, and Convertors

The trailer lights & brake cables Wiring Harness Color Chart illustrates the basics of color-coding. Paradoxically, we believe that the white wire is actually the ground wire. You should connect the white cable to the vehicle ground and trailer frame. The brown wire is used to run to the taillights. This wire also runs to the clearance/identification lights as well. The right turn indicator wire is the green (think starboard) and the yellow is for the left.

Do not use household “wire nuts”. To prevent corrosion, connect your lights using waterproof adhesive-lined BUTT connectors. Ancor Stainless Steel Wire Cutter Crimper Crimper is a top-quality wiring tool.

Japanese, American, and European vehicles use separate circuits that turn and stop. A five-wire-to-4-wire converter will be required for vehicles that use amber rear turn signals or a different area of their light fixture for turning and stopping. These are very affordable and can be used as an integral part of the tow vehicle wiring harness.

LEDs or Incandescents

LEDs solve many of the problems with conventional trailer lights. These lights burn out from vibration, cold water, and require more electricity. These are the advantages of LEDs:

Higher life expectancy LED lights offer a higher life expectancy than incandescent lighting. They have a 100,000 hour rating, while those of incandescent lights last for 3,000 hours. Furthermore, the filaments in LED lights are not susceptible to vibration damage. This means that your bulbs won’t be needed to be replaced and your trailer will likely last for a long time.
LEDs resist submersion and road grime. The lenses of LED lights are permanently sealed in a polycarbonate lens. This prevents any bulb bases from corroding or being damaged.
No thermal shock: LED lamps generate very little heat and so thermal shock caused by immersion is not a problem.
Minimal voltage drop LED lights draw 1/8th as much current as similar incandescent bulbs, so the voltage drops are minimal.
Low profile: LEDs are extremely low-profile, so there is less risk of collision damage with protruding lights.
LED lights go on immediately.

Waterproof Lights

A submersible lamp allows water to get into the unit if it is submerged. The bulb and socket are protected with an air pocket created by the “Belljar principle”. This only allows a small amount of water into the socket, and does not allow for water to touch the bulb. Some of these lights have waterproof “capsules”, which protect the bulbs against corrosion and thermal stress.

Lights that have waterproof properties, such as the Sealed Oval Trailer Light Kit and Sealed Oval Trailer Light Kits, are sealed to prevent water from getting inside. LED lights can be sealed permanently.

Harness for Crossover or Split Wiring

Most trailers have a “splitY” wiring system. This harness splits at trailer’s tongue and runs along each side of the frame. This harness is standard on all our Trailer Lighting Kits.

The wiring harness that runs between the taillights and the trailer’s side may be called a crossover wiring.

How to inspect your lights

Do a walk-around inspection of your boat’s lights before you begin to transport it. You will need a helper to use the turn signals, taillights or brake lights controls. It is recommended that you inspect the trailer at least once per season. Check every inch of your wiring harnesses. Then, secure any loose sections to trailer’s frame with wire tie or cable clamps. Inspect the wiring for potential short circuits. Examine the wiring plug at its coupler end. Clean the contacts with 400-grit paper and then lubricate it with dielectric grease.