Thinking About Headlight Assembly Replacement? Discover the Advantages & How-To!

WHAT IS A HEADLIGHT ASSEMBLY?
A headlight assembly, commonly referred to as the headlight, is a crucial vehicle component responsible for providing illumination for nighttime driving and visibility in poor weather conditions.
- The parts in the headlight assembly
A headlight assembly usually includes multiple parts: headlight housing, headlight bulb, turn signal bulb, headlight lens, headlight reflector/Projector.
- The categories of headlight assembly
The common types of headlight assemblies on the market can be divided according to the following Four types: Types of headlights based on the headlight housing, Types of headlights based on the number of bulbs, Types of headlights based on bulb type, OEM and aftermarket headlight assembly.
Types of headlight assembly based on the headlight housing
(1)Reflector Headlights: The bulb in a reflector headlight is encased in a bowl-like case. The bowl-like case has mirrors installed that reflect the light onto the road.
(2)Projector Headlights: These headlights also consist of a bulb that is enclosed in a steel case that has mirrors. It increases the brightness of the beam of light, and hence, projector headlights produce better illumination.
Types of headlight assembly based on the number of bulbs
Non-Quad Headlights: Non-Quad headlights have a single bulb in each headlight.
(Note: Quad headlights and non-quad headlights are not interchangeable because the wiring inside is specific to each type.)

Types of headlight assembly based on bulb type

OEM Headlight Assembly Aftermarket Headlight Assembly
OEM parts are original parts with the same specifications and performance as original.
Aftermarket Headlight Assembly
Aftermarket parts are manufactured by third parties that are not related to the car or the original manufacturer of the part. But they're not for everyone. They often add additional features and upgrades in lighting performance or aesthetics compared to the original part. At the same time, it can also help you customize your car according to your own preferences.

WHEN TO REPLACE?
Over time, the bulbs in various parts of your headlight assembly will turn yellow or burn out, while the headlight assembly (or lens) will wear out or be damaged by a collision, and the headlight housing will not be tight enough to create water mist or even water pooling.
A car headlight should be replaced after an average time of 2,000 hours and 3,000 hours. In simple terms, you should replace your car's headlight when the emitted light is not enough to see in the dark, or it is giving you constant trouble.
A broken headlight assembly with a dramatic impact on daily driving and lighting usage.
- Dimmed or burned out headlight bulbs mean you can't see the road at night or in harsh natural conditions, and other drivers can't see your driving movements clearly, which is obviously a very serious safety hazard. If you don't fix them, it could mean an expensive ticket from your local authorities.
- In addition, modern headlights are plastic components. The plastic lamp housing will begin to oxidize and deteriorate due to time, weather, and the heat of the bulb. As a result, the textured lens can scatter the light from the bulb, preventing the beam from effectively illuminating the road ahead.
The headlight assembly is vulnerable to damage in various ways during its service life. If any of these conditions are present in your headlight assembly, it's definitely time to fix them!
Bulb yellowing or even burned out |
Yellowing and discoloration of the lens |
The long-term water in the lens cannot be discharged |
The lens is not airtight and often fogs up |
Headlight assembly severely damaged |
ADVANTAGES OF REPLACING HEADLIGHT ASSEMBLY
Main functions of the headlight assembly
PROTECTION: The headlight housing helps keep the bulb in place in the car and keeps out dust and particles, so that It will prolong the service life of the front lighting.
LIGHTING: Good front lighting and turn indicator lights provide safety for your daily travel and driving movements, allowing pedestrians and drivers around you to clearly capture your driving trends.
REFLECTION: Reflectors catch light and reflect it onto the road. Therefore, these headlights are easily recognizable. With the headlight lens, it is more helpful to protect the bulb and cover the reflector.
Benefits to replacing your headlight assembly
When replacing the headlight assembly, it is necessary to refer to the oxidation degree of the headlight. Often, a simple cleaning procedure can restore them to like-new condition, primarily removing oxide layers and polishing the plastic lenses. However, if your headlight assembly is badly damaged, you may choose to replace it entirely.
There are two common headlight assembly replacement parts on the market---OEM headlight assembly and Aftermarket headlight assembly.
- Aftermarket headlight assembly
The aftermarket headlight assembly is currently the most efficient headlight assembly on the market. The brightness is many times higher than that of the OEM, so the replacement cost is high. If you are upgrading from OEM bulbs to LED bulbs, you may experience electrical system issues. Therefore, aftermarket LED lights add new wiring to solve problems with the electrical system. Aftermarket headlights won't ruin your electrical system, but they can be an inconvenience. With OEM headlights, you never have to worry about this.
- OEM headlight assembly
Compared with the low substitution of the aftermarket headlight assembly, OEM headlight assembly has the characteristics of original factory configuration and complete performance, and more importantly, the price is attractive! OEM Headlight assembly replacement will fit without any issues. Meanwhile, aftermarket headlights are rarely covered under warranty, while OEM headlights are. So, the OEM headlight assembly has become the first choice for many car owners to upgrade and replace components.
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Replace the entire OEM headlight assembly and you'll find lots of extras!
- Improve the output and visibility of headlights, enhance the beam scattering effect at night and in complex environments, and increase driving safety.
- The new OEM headlight assemblies are built with high quality materials
- Will fit your vehicle perfectly
- Get a sophisticated and smooth look at the best price
- The mold is made by the original factory, the size, line, joint and so on are consistent with the original factory
Not only will your headlights work better after the replacement, but you'll also be surprised how much newer your car will look when equipped with bright, clean headlights! Therefore, replacing the headlights with new ones is more rewarding than investment!
Characteristics of headlight assembly need to have
An excellent OEM headlight assembly must play the ultimate role in both main functions and installation adaptation. Below are our recommendations for features to choose the right assembly for you.
- Excellent function
Equipped with headlight angle adjustment knob, the best viewing angle can be adjusted through the knob. The Reflector structure uses reflective structures to project light from a light source onto the road in a desired shape, producing a larger beam pattern that covers a larger surface area. Therefore, the reflection efficiency is extremely high and the brightness loss is small. It ensures maximum light output and is 180% brighter than original headlights.
Better visibility, increase visibility in blind spots, reduce traffic accidents and ensure driver safety.
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- Stable performance
IP65 Waterproof: The headlight is made of fully sealed PC plastic with tensile/impact strength, IP65 protection level, even temporarily immersed in 1m deep water in rainy days will not cause harmful effects. IP65 is rated waterproof and durable to withstand all weather conditions, good rigidity and dimensional stability prolong the life of components.
ABS Plastic Housing and Polycarbonate lens materials increase the reflective effect and durability, increase the protection of the bulb, and improve the performance of wear resistance and impact resistance.
- Exquisite appearance
Replacing the yellowed and old original car assembly with a simple and elegant headlight assembly can provide a more advanced and fashionable body appearance.
- Compatible with the original
Complies with strict DOT and SAE safety standards required by OEM manufacturers and undergoes rigorous testing to ensure your safety. Compatible with original manufacturer's specifications for seamless replacement.
- Quick installation
The headlight housing is a perfect replacement for original parts, quick and easy installation (within 20 minutes), drilling and modifications are not required, just use your vehicle's existing wiring, switches and screws to install the headlight.
It is worth noting that when you purchase the headlight assembly for replacement, you need to pay attention to the choice of the original matching model and the bulb model. If you need to replace the OEM headlight assembly, you can refer to the model diagram of the headlight assembly below. They are all compatible with the original manufacturer's specifications and can be replaced seamlessly. New upgrades will be available soon!
RECOMMENDATION OF THE HEADLIGHT ASSEMBLY
Tips for choosing headlight assembly for your car
Here are some things to consider before choosing a new replacement OEM headlight assembly for your vehicle:
- What is the exact model number of your vehicle?
- Do you need extra beams?
- Can you install them yourself?
- Is the installation process difficult?
- Consider whether it's easier to use a standard halogen bulb or something fancier like a xenon, which produces brighter light with less energy consumption.
- Don't forget about the warranty information - what it covers and what it leaves out.
- If you need to upgrade the original halogen bulbs to LED bulbs, please refer to: AUXITO VEHICLE BULBS SIZE CHART
HOW TO REPLACE HEADLIGHT ASSEMBLY
How much does it cost to replace a headlight assembly? Each headlight can cost anywhere from $200 to $1,000, depending on how removable the assembly is. And sometimes you will pay some extra labor costs for the installation, which can make the whole process even more expensive.
Installing a headlight assembly is a simple job that any DIY enthusiast can do. However, it would be helpful if you had an installation reference to make sure you don't forget anything important when it comes to replacing your headlights. If you are not confident in installing your headlights yourself, we always recommend that you have a professional technician install them for you.
(NOTE: The headlight assembly installation steps refer to the 2003 Toyota Tacoma, and the headlight assembly of different models may have differences when replacing.)

Step 1: Remove the old headlight assembly
Locate the two bolts on the top of the headlight assembly and remove them with your wrench or socket. Set them some place safe.
Step 2: Disconnect the assembly
Slide the headlight assembly out and disconnect the electrical connectors from the headlamp and parking light sockets.
Turn the headlamp retainer ring counter-clockwise to remove it from the headlamp. Remove both bulb sockets from the headlamp assembly.
Step 3: Disconnect electrical
Disconnect the electrical connectors from the headlamp and the parking light sockets.
Step 4: Remove the old assembly
Remove the screw on the top of the assembly between the headlamp and the parking light. Remove the old headlamp wiring harness. Be sure not to touch the bulbs with bare fingers—especially the headlight bulb. Nitrile gloves work great for this.
Step 5: Replace the assembly
Transfer the headlamp wiring harness and rubber to the new assembly by removing the screw to make room as we did on the old assembly.
Step 6: Connect the new assembly
After securing the bulbs in their sockets, they can be inserted into the new assembly. Secure the headlamp by turning the retainer ring clockwise onto its socket. Reconnect the electrical connectors to the headlamp and parking light sockets.
Step 7: Reinstall the new headlight assembly
Position the assembly so that the bracket tabs are aligned with their slots and slide the headlamp inward to engage the tabs. Replace the two bolts at the top of the assembly. If you also need to replace the headlight assembly component on the other side, repeat the above steps.
For a detailed replacement tutorial, please refer to the headlight assembly installation video.
WHAT ADJUSTMENTS NEED TO BE MADE AFTER REPLACEMENT?
Headlight angle adjustment
After replacing your headlight assembly, you need to check your headlight alignment. In addition, the headlight beam may be misaligned due to wiring problems, a bad fuse, or damage to internal components. If your headlights are not aligned properly it can affect your visibility and even dazzle or blind other drivers if they are angled too high. This is why it is important to adjust your headlights when they are misaligned.It is recommended to check this Blog (Headlight Adjustment Aiming Wall Chart) for proper headlight aiming methods and procedures.
Note: This adjustment recommendation is not unique to the replacement of the AUXITO headlight assembly. In order to ensure the safety of night driving, the position of the headlight beam irradiation is listed as a mandatory safety inspection project. Replacement of all other brands of aftermarket headlight assemblies will require a check of headlight aiming.
Headlight wiring modification
(Note: This step is not necessary unless modifications have been made after installation)
- If you've made changes to your headlights or attempted a DIY repair after replacing the headlight assembly, it's likely that your headlights have dimmed, misfired, or stopped working entirely. Therefore, after installing the new headlight assembly, your wiring of headlights needs to check.
- You may need to adjust your wiring, get a new wiring harness, replace a fuse, or make other electrical repairs. At this point, you will most likely need to seek out an experienced mechanic to diagnose your headlight failure and work with you on a repair plan.
MAINTENANCE
Periodic inspection
- Check the lights: The first step in properly maintaining your headlights and brake lights is to check your lights regularly and frequently. This can be a quick walk-through where you check the lights for any malfunctions, uneven darkness, and other defects.
- To replace damaged or defective parts: If your headlights or taillights are damaged, damaged or not working properly, you need to replace them immediately. Driving with broken headlights or brake lights could result in a ticket.
Surface maintenance
Case Cleaning:
- Using tape, mask off the area around the headlight to avoid scratching the paint.
- Clean the surface (using car soap) to remove dirt. Dry the surface and look for hazing, yellowing, or cracks.
- Wet the surface and sand the lens with 1000-grit sandpaper.
- Seal the lens with a wax sealer.
Case Antioxidant Protection:
Park Under the Shade or Garage away from UV rays (film covers can be used if no shade is present)
Keep your headlights clean by removing any built-up residue and protecting them with polish and ceramic coatings.
In-shell maintenance
- Use a special soap solution for car lens cleaning, add water to the lather, rinse the inside of the Headlight Lenses, and rinse with running water.
- Two more quick rinses with distilled water
- Dry the lens vertically with compressed air (this can speed up the drying speed)
- After thoroughly drying the inside of the lens, you can see some water stains and dust remaining on the lens when facing the sun. In order to make your lenses brighter and cleaner, it's best to swish and get the stuff out
CONCLUSION
All in all, OEM headlight assembly replacement parts are a quick replacement for you to replace your old damaged original. Regular inspection, maintenance and replacement of the headlight assembly with the appropriate model are not only to ensure the normal use of your front lighting, but also an important guarantee for the safe driving of your vehicle.
Q&A
- Why do you have to replace the entire headlight casing when it’s just the bulb that has burned out?
In order to ensure that the new bulb is properly protected and securely in place, it's often recommended to replace the entire headlight casing. Additionally, it can be difficult to remove and replace just the bulb without damaging the casing, so it may be more cost-effective in the long run to replace the entire assembly.
- Large variations in daily temperature. As the dew point or humidity increases, the vapor tends to accumulate easily together. Leaks in the sealing ring on the bulb or bulb socket. What should I do?
Condensation is a normal process and can happen especially after a change in weather. The misting within the headlight will dissipate on its own. However, if you have excess amounts of condensation then there could be an underlying issue with the headlight itself.
These are common occurrences and there are some useful solutions below:
- Check all vents for blockage. Turn on the headlights for 20 minutes to raise the temperature of the headlights and evaporate the condensed water
- Remove the bulb to evaporate the water inside the sell. use a hair dryer or heat gun for low-temperature heating.
- Put the hygroscopic silica-gel desiccant in the headlights
- How to prevent water from flowing into the lamp housing?
If no damage is found to the headlight, then it's time to consider the possibility of a broken seal. Don't panic - it's also easy to fix. You can go to the repair company to seal the headlight assembly or replace it with a new headlight assembly.
Last but not least, we offer a 2-year warranty and professional installation instructions.
👉👉👉Any questions about our products, please feel free to contact us! Our customer service team will be glad to help you. We pride ourselves on our ability to resolve your issue the first time around and can be reached us with email: support@auxito.com.
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