What Is a Tail Light?

A tail light is a red lamp mounted on the rear of a vehicle to indicate its presence. It is also used to warn other drivers to watch out for the car.

If your tail lights are not working, it is important to fix them right away. The problems that can affect your tail lights include a faulty bulb, fuse or wiring.

The light bulb

The light bulb is a remarkable invention, turning electricity into bright illumination for hours on end. It contains only a few parts, and the whole thing is pretty simple. The thin filament tail light wire is made of hard-to-melt metal, usually tungsten, and it’s encased in a glass bulb filled with inert gases to prevent the wire from disintegrating. When electrical current passes through the filament wire, it heats it up to a high temperature and glows.

Most modern car models have separate bulbs for the tail lights and brake lights. The reason is that if both bulbs burn out, the lights won’t turn on.

Fortunately, a bad bulb is easy to diagnose and replace. You can get to the tail light bulbs by removing the trunk upholstery and exposing the bulb and fuse connections. Be sure to use a fuse tester or another bulb test device to verify the fuse is good before you start working on the wiring.

If the tail light and the 3rd brake light are both inoperative, it’s likely that you have a problem with the hydraulic switch. This switch, mounted somewhere in the line between the master cylinder and the fluid reservoir, is responsible for increasing the pressure of the brake fluid and thus activating the lights. Using a multimeter, you can check the switch for continuity and a ground. If everything checks out, the problem will be in the wiring.

The lens

A tail light is a pair of lights, usually red, mounted at the rear part of a vehicle to warn following vehicles that the car is there. They are switched on only after the front brake lights have been activated and help to prevent being rear-ended by another driver.

The lens of a tail light is made of transparent glass and has a curved shape. This helps to direct the light that is being emitted by the bulb. The glass is often painted with a reflective coating to increase the amount of light that is being directed towards the road.

As time goes by and the vehicle is driven, it’s common for the lens to crack. This is due to the refraction of the rays of light as they strike the surface of the lens. The cracks can then progressively get worse and eventually break.

If the cracks are not repaired, water can leak into the housing and potentially short out the electrical system inside of the car. As a result, it’s important to regularly check the condition of the lenses.

One of the best ways to do this is by using a product such as our Speed Lens Restorer Kit. This kit contains everything you need to clean off light scratches, sun damage and oxidation from your vehicle’s lenses in 15 minutes or less.

The housing

Tail lights are an important safety component for your vehicle. They alert other drivers that you’re slowing down and can help to reduce accidents. They are also a great way to customize your truck. Unfortunately, they can be damaged by cracked lenses, broken wiring, and faulty bulbs. Regular checks will help to ensure they are functioning properly. In addition, your tail lights may require a replacement fuse or bulb socket. If this is the case, you should replace them immediately.

First, make sure you have a multimeter and a ratchet on hand. You may need to remove the panel to access the tail light. Before you begin, make sure you’re in a well-lit area and wear nitrile gloves. Next, remove the fasteners (screws or bolts) and put them somewhere safe.

Carefully inspect the tail light and look for any cracks in the lens or housing and any splits or separation in the sealant between them. Mark any areas that need repair.

Use a heat gun to soften the sealant around the perimeter of the lens and carefully separate it from the housing. Once it’s cool enough to tail light handle, apply new sealant using the application tips included with the product you purchased. Let it sit as long as the instructions suggest before reattaching the lens.

The wiring

A wire harness connects the tail lights to the vehicle’s switch. When a light is turned on, the switch sends power to the relay, which then powers the tail lights. In some vehicles, the relay also controls the brake lights. In this case, the same fuse is used for both the tail and the brake lights. If the brake lights are not working, it is likely because one of the bulbs has failed or the wiring has melted.

Many manufacturers use LED bulbs in their tail lights to improve the look of the rear of the vehicle and save on energy costs. These bulbs are brighter and more efficient than traditional incandescent bulbs, so they don’t burn out as quickly. They can also emit a stronger, more uniform beam of light.

If you are replacing a tail light, make sure to disconnect the old bulb from the socket and test the new one. You should notice that the new bulb is a different color than the old one, and this will help you identify the correct wire to connect to. If you are using a 3-wire bulb, the one remaining color will be the positive brake wire. If you are using a 4-wire bulb, the other color (excluding ground) will be the positive turn signal wire.

You can splice the wires by twisting them together and then covering them with electrical tape. You may want to consider using a non-conductive grease in the bulb sockets to seal out moisture and prevent corrosion.