The Complete Guide to G37 Headlights: Maintenance, Upgrades, and Replacement
For owners of the Infiniti G37 coupe or sedan, the vehicle's headlights are a critical component of both its distinctive aesthetics and its nighttime safety. Whether you are dealing with a failed bulb, foggy lenses, or simply seeking a performance and style upgrade, understanding your G37 headlights is essential. This comprehensive guide provides everything you need to know about G37 headlights, from basic maintenance and repair to advanced aftermarket upgrades, ensuring you make informed decisions for your vehicle.
The Infiniti G37, produced from 2007 to 2013, features sophisticated lighting systems that evolved slightly over its production run. The standard system uses powerful High-Intensity Discharge (HID) bulbs for low beams and halogen bulbs for high beams and turn signals, housed in complex reflector/projector assemblies. Familiarizing yourself with this setup is the first step to proper care and modification.
Understanding Your G37's Factory Headlight System
The factory headlights on the G37 are more complex than simple halogen units. From 2007 to 2010, the G37 Coupe and Sedan used a bi-xenon system where a single HID bulb and a mechanical shutter provide both low and high beams. The 2011-2013 models, particularly with the Premium or Journey packages, often featured advanced Adaptive Front-lighting System (AFS) headlights. These headlights swivel slightly in the direction of your turn, improving illumination around corners. Identifying whether your G37 has standard HID or AFS headlights is crucial before purchasing replacement parts or attempting repairs. The AFS system involves additional motors and sensors, making components more expensive and complex to service.
Common G37 Headlight Problems and Solutions
G37 headlights are generally robust but are known for a few specific issues that owners will likely encounter.
Fogging or Moisture Inside the Headlight Assembly: This is a frequent complaint. Minor condensation that clears after the headlights have been on is often normal due to ventilation. However, persistent pooling of water indicates a failed seal. The fix involves removing the headlight assembly, thoroughly drying it, and resealing the lens-to-housing bond with a high-quality butyl rubber sealant. Ignoring chronic moisture can lead to bulb failure, socket corrosion, and damage to expensive internal components like ballasts or AFS motors.
HID Bulb or Ballast Failure: HID bulbs have a long lifespan but eventually fail, often by dimming, flickering, or changing color before going out completely. The electronic ballast, which provides the high voltage to ignite the bulb, can also fail. Symptoms include the bulb not lighting, or turning on and off intermittently. Diagnosis typically requires swapping the suspect bulb or ballast with the unit from the opposite side to see if the problem follows the component.
Yellowed, Hazy, or Cracked Headlight Lenses: UV exposure and road debris gradually oxidize the polycarbonate plastic lenses, drastically reducing light output and ruining the car's appearance. While temporary restoration kits exist, the most permanent solution for severe oxidation is professional lens sanding and polishing, followed by a durable UV-clear coat application. For cracked lenses, replacement is necessary.
Step-by-Step: Replacing G37 HID or Halogen Bulbs
Replacing bulbs is a common DIY task. Always replace bulbs in pairs to ensure even light output and color temperature.
- For Low Beam HID Bulbs (D2S type): You must access the back of the headlight assembly from within the engine bay. After removing a dust cover, you will find the bulb held in place by a metal clip. Disconnect the wiring harness before releasing the clip. Never touch the glass quartz of a new HID bulb with bare fingers, as skin oils can create hot spots and cause premature failure. Use a clean cloth or gloves during installation.
- For High Beam and Turn Signal Halogen Bulbs: These are more straightforward. Access the bulb socket, usually by twisting it counter-clockwise, pull the old bulb straight out, and insert the new one without touching the glass.
Upgrading Your G37 Headlights: Options and Considerations
Many owners seek to improve upon the factory lighting performance and style.
HID Bulb Upgrades: The stock HID bulbs are around 4300K, producing a bright white light with a slight yellow tinge. Upgrading to 5000K or 5500K bulbs yields a purer, crisper white light that closely matches daylight, improving contrast. Avoid bulbs advertised at extremely high Kelvin ratings (e.g., 8000K or 12000K), as they produce dimmer blue or purple light that is illegal in many areas and reduces usable road illumination.
LED Bulb Conversions: LED bulbs for the high beams, fog lights, and turn signals are popular upgrades for their instant-on light, whiter color, and longer lifespan compared to halogen. Plug-and-play LED kits for the low-beam HID sockets also exist but require careful selection. A critical factor for any LED conversion is ensuring the bulb is designed to properly align its LEDs within the headlight's focal point; a poorly designed LED will produce glare and scattered light patterns, blinding other drivers.
Complete Aftermarket Headlight Assemblies: The most dramatic upgrade is replacing the entire headlight unit. The aftermarket offers G37 headlights with blacked-out housings, LED accent strips (DRLs), and updated projector lenses. Some high-end options feature complete LED or modern bi-LED projector systems. When considering aftermarket assemblies, prioritize quality from reputable brands. Cheap units often suffer from poor light output, rapid lens yellowing, and water leaks, negating any aesthetic benefit.
The AFS System: Special Notes for Equipped Models
If your G37 has AFS, you must be aware of system-specific issues. AFS malfunctions are commonly triggered by faulty leveling sensors (attached to the suspension), damaged wiring, or failed steering angle sensors. The system will often store a diagnostic trouble code and may disable the swivel function, sometimes defaulting the headlights to a low position. Diagnosing AFS problems typically requires a professional scan tool that can interface with the AFS module.
Cleaning and Protecting Headlight Lenses
Regular cleaning is vital. Wash lenses with the same car wash soap used on your paint, avoiding harsh abrasive cleaners. Apply a spray wax or dedicated plastic sealant every few months to slow the oxidation process. For already-oxidized lenses, a professional restoration is the most reliable long-term solution.
Legal and Safety Considerations
Any headlight modification must prioritize safety and legality. After any bulb replacement or upgrade, you must check and correctly aim your headlights. Misaligned headlights, whether too high (causing glare) or too low (reducing visibility), are dangerous. Most jurisdictions have strict regulations regarding headlight color, brightness, and where certain lights can be mounted. Non-compliant modifications can result in fines and failed vehicle inspections.
In summary, maintaining and upgrading your Infiniti G37 headlights involves a blend of practical DIY skills and informed purchasing decisions. Addressing common issues like moisture and oxidation promptly preserves both safety and value. For upgrades, focusing on quality components from trusted manufacturers and ensuring proper installation and alignment will guarantee results that are not only visually pleasing but also significantly enhance nighttime driving safety. Whether you are performing a simple bulb change or installing a full custom setup, this knowledge empowers you to keep your G37's vision clear and its presence unmistakable on the road.