Reverse Light Wiring: How to Wire A Reverse Light

FACTS CHECKED BY  Jose George​

As you reverse your car, pedestrians can be behind you or other vehicles. To indicate them, the auto manufacturers use “bulb reverse lights,” which suggest that you are about to reverse the car. That way, many hazards are handled. Let’s see the reverse light wiring to see how it works.

Low Voltage Wiring
Low Voltage Wiring

What is a reverse/backup light?

A reverse/backup light is a wired light available at the car’s rear so that it only turns on when you activate the reverse gear. Moreover, a light switch selector mechanism attaches to this switch circuit. Hence it illuminates your reverse lights when you move into reverse.

However, as the country of manufacture changes, a car may have fewer or more reverse lights. There is now only one reverse light available on European automobiles as it is on the driver’s side. (For Australia, it has to be on the right-hand side.) Also, a fog lamp could be used by the opposing side. The majority of American-made cars will have two reverse light globes.

Benefits of a reverse/backup light

Your car’s reverse lights are a crucial safety feature since they let other vehicles and pedestrians know that you’re going to back up. Similar to Brake lights, backup lights help to signal other cars, which helps prevent severe collisions and accidents.

The primary goal was to increase reverse lights’ visibility in the mist. The majority of current automobiles must have two reverse lights. It is so that design considerations may quickly and easily replace tail lights.

That’s not all, though. When driving, you need a well-lit environment to determine how much and in which direction to reverse. Additionally, the backup light bulb gives you enough light in entirely dark areas to determine how much and where to change. The backup light offers a benefit when a modern vehicle has a reversing camera since it illuminates the space sufficient for the cameras to get a clear view.

Car rear indicators or rear tail lights

Car rear indicators or rear tail lights

Reverse light legal issues 

One reversing light is not against the law. In older models, European automakers only utilize one reverse light. Asian automakers, however, employ two reverse lights. There is no necessity to have a Backup Reverse Light lamp because it is legally classified as an additional light rather than a required light. However, it continues by stating that if you install an optional light, it must adhere to laws.

Adding reversing lights

Providing an aftermarket set is a good idea if you did not fit your car with reversing lights when it was being manufactured.

Types of light

Reversing lights come in a wide variety; therefore, it is wise to browse around to discover the most terrific deal and model for your vehicle. The bumper, below or above it, is where you can find the most typical reversing lights. They can be fastened to the bumper using clamp-on hardware or nuts and bolts.

The flush-mount variety of backup light units is another bulb you can attach to any acceptable flat metal surface, such as the plain rear panel over the bumper. Also, it is fixed in place either with small nuts and bolts or self-tapping screws.

Existing wiring

You might discover that the rear light’s entire cabling (and occasionally their bulb holders and lenses) are already available on some autos. Purchase a gearbox switch, install the light fixtures (or just the bulbs), and then join the existing wire. To find out if this is feasible with your car, consult the manual or your local dealer.

You will need to install a manual on/off switch to the dash if your car doesn’t have reverse light wiring; this button should also include an indicator to let you know when the reverse lights are on. Remember that it is not legal to move forward while displaying a white light to the back.

Fitting process

To fix the reverse light, you can follow these steps.

  • Find an appropriate place on the bumper to bolt the clamp and fix the light unit. You need separate ground wire that you can pass through drilling a hole.
  • Check the manual to find the gearbox position with a blank plug or plate. Unscrew the plug and fix the new switch.
  • Disconnect the battery and place a wire from the ignition system to the gearbox switch terminal. Fit an in-line fuse, run its wire under the car carpet, or trim it.
  • Place a grommet where feed wire enters the body after drilling a hole. To the light unit, connect the wire.
  • Use a Scotchlok connector to attach an additional wire to the gear switch feed cable if you are installing two lights. This cable should connect to the second light fixture. Test the light output after reconnecting the battery.

Fixing a reversing light

The circuit of a reversing light is simple. It has one or more rear light units that you can operate using a switch. So, in case of any malfunction, you can easily root out the issue. Moreover, in most cars, the button mounts on the gearbox and operates when you select the reverse gear. After manufacturing the vehicle, you must climb manual equipment on the dashboard if you add the reversing lights.

Blown bulb

The most frequent issue is a blown bulb. Take it out of the holder, then use a fast connection wire to join the battery terminals to test it. If the bulb turns on, another circuit component is not acceptable.

Fuses

The fuse guarding the reverse lights frequently also protects additional accessories. Replace the fuse and retry the test if neither of these works. It may be simpler to have an auto-electrician locate the short circuit if the fuse explodes as you test it since this indicates that there is one elsewhere.

Current check

Check the live wire in the bulb socket while attaching the test lamp to a reliable earth point. If the test bulb illuminates, the bulb is receiving current. If the lightbulb has a different earth line, there is where the problem must be.

Wiring Check

Find the color and location of the reverse wires and connect them slowly. You must recheck the rest of the circuitry if no current is flowing to the bulb holder. Plugging in a new wire might solve the problem if you discover it is within the loom.

Switch test

Test the gearbox switch if there isn’t any current flowing through the wires. Also, two switch connections will be there on a manual automobile. There will be four terminals on an automatic, two of which are for the inhibitor circuit and shouldn’t be disturbed. To identify the proper terminals for testing, consult your manual.

reverse light wiring diagram

Caption: reverse light wiring diagram

source: https://www.howacarworks.com/illustrations/reversing-light-switches 

Auxiliary reverse lights, are they legal?

Additional lights that are found on the outside of your car are the auxiliary lights. When you need more vital lighting, these lights supplement the car’s standard headlights and fog lights.

Unfortunately, unless such lights strictly adhere to ADR requirements in the design and installation position, it is often not legal. It is because the light produced by these lamps is more significant than what is necessary for on-road use. Since they are typically not ADR or ECE authorized for purposes such as reversing lamps, this is why.

The three most important considerations when installing auxiliary reverse lights on your car are the following.

  • Cars under 6 meters must have at least one reverse light.
  • Also, they have to be at least 250mm and not more than 1200mm above the ground.
  • Any lamp used when driving a vehicle on the road needs to have ECE or ADR approval and have that mark visible.

In addition, ADR13 has strict regulations about reverse lighting. Installing any other LED Light Rod as a rear light will probably get you a caution unless your car is equipped with an ADR compliance reverse light.

How to wire Auxiliary Reverse Lights?

When you wire Auxiliary Reverse Lights, you may need some switches.

Reverse light TOGGLE SWITCH wiring

The single pole, double throw switch, or SPDT may be your best option. Your auxiliary b/u lights will be connected to your current reverse light circuit through one leg of the switch. If you want them to operate with the engine off, the other line will directly energize them from the cell or a bar.

 AUXILIARY REVERSE LIGHT RELAY WIRING with SPDT switch (substitute your reverse lights for the headlights part)

Caption: AUXILIARY REVERSE LIGHT RELAY WIRING with SPDT switch (substitute your reverse lights for the headlights part)

source:  https://expeditionportal.com/forum/threads/back-up-light-question.155580/

Reverse light relay wiring

Depending on how much energy your aux b/u lights consume, you may or may not need a relay in the circuit. You usually don’t need a relay for power consumption under 60 watts. If your aux lighting is more powerful than 60 watts, you need one standard Bosch relay. With this method, diodes are not required.

reversing lights with or without a relay

Caption: reversing lights with or without a relay

Source: https://www.pinterest.com/pin/401946335495525193/ 

Conclusion

Reverse lights are essential for any vehicle. So, you can fit them on existing wiring or set a new frame for them. Moreover, after knowing the wiring, you can also repair them by testing their different components. Here at Cloom, we offer wiring harnesses and cable assemblies to make your tail light assembly safe and reliable.

Get a free Cable Assembly Quote.